Police officers secure a street during a raid in the Molenbeek neighborhood of Brussels, Belgium, Friday, March 18, 2016. AP 
 
 More than two dozen people were reported killed and even more wounded after explosions ripped through Brussels airport and metro stations across the city Tuesday morning, in attacks for which the terror group ISIS has claimed responsibility. 
 
 The attacks came days after Salah Abdeslam, a suspect in last year's terror attacks on Paris, was arrested in Brussels, the capital of Belgium and heart of the European Union. 
 
 An expert who met with Belgian counterterrorism officials last week told Business Insider that the country is overwhelmed by the number of radicalized people who pose threats to the country. 
 
 Matthew Levitt, the director of The Washington Institute's Stein Program on Counterterrorism and Intelligence, said Belgian police have only begun to understand the depth of the country's terrorism problem in the past year. 
 
 "Belgians have a really big problem because they have the largest number per capita of western foreign fighters from any country," Levitt told Business Insider. "The numbers are simply overwhelming." 
 
 The International Centre for the Study of Radicalisation found last year that Belgians contributed 40 foreign fighters to Sunni militant groups in the Middle East per 1 million people, the highest per-capita rate of any Western European country. 
 
 Belgians have contributed more than 400 fighters to extremist groups in Syria and Iraq, according to a 2015 report from strategic security firm The Soufan Group. Of those, more than 100 are thought to have returned to Belgium. 
 
 And it's not just returning foreign fighters whom Belgium has to worry about. People are also becoming radicalized in Belgium, in some cases without ever traveling to the Middle East. 
 
 "Only in the last year have they really come to grips with the fact that this presents not just a problem of [radicalized] people who are returning from other countries but also those who … never leave in the first place and can carry out attacks at home," Levitt said. 
 
 Reuters 
 
 Levitt said that while Belgian counterterrorism police are "quite capable," there are roadblocks to preventing terrorist attacks inside the country. Part of the problem stems from communication within the government. 
 
 "It is a deeply divided government regionally, ethnically, linguistically," Levitt said. "There are multiple parliaments. So it's long been an issue in terms of the level of communication across jurisdictions." 
 
 Another issue is that, until recently, Belgium intelligence agencies focused mostly on EU spying. 
 
 "From an intelligence perspective, they've long been focused on counterintelligence, people trying to spy on each other within the EU," Levitt said. 
 
 Belgium is also limited in what it is allowed to do to spy on its citizens. 
 
 "They have very strict limitations on when certain types of tools, like telephone intercepts, can be used," Levitt said. 
 
 The blown-out windows of Brussels-Zaventem airport after a deadly attack in Brussels, Belgium, Tuesday, March 22, 2016. Peter Dejong/AP 
 
 A Belgian counterterrorism official made a similar assessment to BuzzFeed News last week. 
 
 "We just don't have the people to watch anything else and, frankly, we don't have the infrastructure to properly investigate or monitor hundreds of individuals suspected of terror links, as well as pursue the hundreds of open files and investigations we have," the unnamed official said. "It's literally an impossible situation and, honestly, it's very grave." 
 
 Authorities did make changes after the November terrorist attacks in Paris, which ISIS (also known as the Islamic State, ISIL, or Daesh) claimed responsibility for, but they're still behind. 
 
 Belgian police have been coordinating with French counterterrorism authorities in raids, and the country now has "a much more organized list of people they are most worried about and broken down by categories in why they're worried about them," Levitt said. 
 
 But the problem has been festering for a while, making it more difficult to reign in. 
 
 "They have a problem both in terms of getting on top of the immediate threat that has developed over time and then also moving the needle early in the process and putting in place a 20-year plan in places like Molenbeek to prevent radicalization," Levitt said, referring to a Belgian suburb notorious for Islamic extremism. 
 
 Reuters 
 
 Terrorists exploiting refugee crisis 
 
 ISIS is thought to have an extensive network of terrorists in Europe, some of whom have trained in the Middle East. 
 
 "Ever since the ISIS spokesman called for attacks against the West in 2014, we've see this pick up pace," Levitt said. 
 
 Levitt referred to the attacks last January on French satirical magazine Charlie Hebdo, claimed by Al Qaeda-affiliated terrorists. 
 
 "We're not surprised by what we're seeing in Belgium because right after the attacks on [satirical magazine] Charlie Hebdo [in January 2015], immediately there were raids in Belgium," he said. "We saw not just the 'lone offender' or 'lone wolf,' home-grown, radicalized types of plots. … We also started seeing these foreign-directed plots." 
 
 The Paris attacks were directed by foreign actors. Some of the attackers had trained in Syria before returning to France and Belgium to plot and carry out the simultaneous shootings, bombings, and hostage-takings that killed 130 people and injured hundreds more. 
 
 The Paris terrorists were able to exploit the ease of travel around Europe, which has seen a massive flow of migrants fleeing conflicts in places like Syria and Iraq. 
 
 Europe still hasn't tightened border security enough to prevent foreign fighters from returning and traveling around Europe, Levitt said. 
 
 "Travel within the EU is still quite wide open, and that presents challenges for security officials," Levitt said. "We saw how easily the Paris attackers were able to move to and from Brussels and Paris before and even after the attacks." 
 
 European authorities started cracking down on border security after the Paris attacks, but it hasn't been enough. The Turkish border in particular is quite porous — once a fighter crosses the border from Syria or Iraq into Turkey, it's easy to travel to other parts of Europe, according to Levitt. 
 
 "The security efforts in terms of border crossing are really just now beginning to get the kind of attention they need," Levitt said. 

 BRUSSELS — Within minutes of a bomb blast at Brussels’ main airport, mobile phone and internet networks crashed. 
 
 
 
 After a second attack struck a metro station in Maelbeek, which feeds the main European Union complex, Belgian soldiers, who have been a regular presence in the city center since last November’s bloody attacks in Paris, departed, apparently to join the first responders at both scenes. 
 
 At the Central Police Station, located a few hundred meters from the Gran Place, in the very center of Brussels, dozens of off-duty police both in uniform and plainclothes could be seen reporting for emergency duty, many carrying automatic weapons. A squad of Belgian army members known as para-commandos also deployed and began patrolling various areas in the city center in full combat gear. 
 
 Tuesday’s attack came after a week of tensions throughout the Belgian capital as security forces closed in on Salah Abdeslam, believed by French and Belgian investigators to be the last surviving member of the ISIS cell that carried out the Paris attacks that killed more than 130 people and wounded hundreds more in a multi-pronged attack on the French capital last year. A raid in Brussels' Forrest neighborhood last Tuesday killed an Algerian with suspected ISIS ties, but Abdeslam was believed to have escaped back to his childhood haunt of Molenbeek, a largely Muslim immigrant neighborhood just outside central Brussels. Using a combination of electronic tracking of mobile phones and what investigators say was human intelligence, according to local media reports and terror analysts, security forces cornered, wounded, and arrested Abdesalm last Friday. 
 
 Belgian authorities said early Tuesday afternoon that a massive manhunt was underway in Brussels for individuals they believe were linked to Tuesday's attacks. 
 
 
 
 Belgian counterterrorism officials have been on high alert for years as hundreds of citizens and residents have departed for the battlefields of Syria and Iraq. One Belgian official said that besides the names of hundreds of fighters believed to be abroad, the security services have more than 200 open files related to threats at home and in Europe. But they remain flooded with questions about how and why they missed a key member of the Paris attacks for more than four months, and will have to explain how just four days after his arrest, the country was devastated by a double attack on both the international airport and a metro station that feeds Europe’s central government, hardly areas considered soft or easy targets. 
 
 One Belgian counterterrorism official told BuzzFeed News last week that due to the small size of the Belgian government and the huge numbers of open investigations — into Belgian citizens suspected of either joining ISIS, being part of radical groups in Belgium, and the ongoing investigations into last November’s attacks in Paris, which appeared to be at least partially planned in Brussels and saw the participation of several Belgian citizens and residents — virtually every police detective and military intelligence officer in the country was focused on international jihadi investigations. 
 
 “We just don’t have the people to watch anything else and, frankly, we don’t have the infrastructure to properly investigate or monitor hundreds of individuals suspected of terror links, as well as pursue the hundreds of open files and investigations we have,” the official, who spoke on condition of anonymity because he was not authorized to speak to the media, said. 
 
 “It’s literally an impossible situation and, honestly, it’s very grave.” 
 
 The streets of Brussels were relatively calm by Tuesday afternoon. Some foreign tour groups continued to visit sites in the city’s historic district. But one Belgian who gave his name as Andre, a 42-year-old telecommunications and marketing executive for the Belgian telecom firm Mobistar, said that the historical government divisions between the southern French speaking and northern Dutch speakers that have often left Belgium’s government fractured and ineffective were largely responsible for the country’s inability to prevent the sort of terror attacks that struck on Tuesday. 
 
 “This is what happens when you don’t have a real government and a divided bureaucracy,” he said. 

 The atrocities in Brussels this morning broke disturbing new ground. Until now, Belgium has been a incubator of jihadism rather than itself a target for indiscriminate, home-grown terrorism. The May 2014 attack on the Jewish Museum in Brussels, in which four people died, was more anti-Semitic than “anti-Belgian” in motivation. It was carried out by a French-born Islamist radical. 
 
 Today's attacks are different. The chosen targets were Belgian, although also clearly international. The bombers struck the American departure area of Zaventem airport and a metro station 200 metres from the headquarters of the European Commission. 
 
 Brussels has become, for complicated reasons, one of the epicentres - if not the epicentre – of jihadism in Europe. The 13 November attacks in Paris last year were, as we know, planned and carried out from Brussels. Their ringleader, Abdehamid Abaaoud, was born in Belgium. The runaway surviving Paris attacker captured last week, Salah Abdeslam, is a French citizen of Moroccan origin who has spent his whole life in Molenbeek, the sprawling 40 per cent Muslim commune (borough) which stretches west from the centre of Belgian’s capital. Proportionally, there are more young Belgians – including many converts – fighting with Isis and other jihadist groups in the Middle East than from any other European Union nation. 
 
 The timing of yesterday’s attacks suggests that the motive might have been revenge for Abdeslam’s capture. The truth may be more complicated. 
 
 In pictures: Terror attacks at Brussels airport 
 
 
 
 
 
 
 
 30 show all In pictures: Terror attacks at Brussels airport 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 1/30 A man carries an injured person in Brussels Airport, after explosions ripped through the departure hall 
 
 2/30 Travellers get to their feet in a smoke filled terminal at Brussels Airport after explosions 
 
 3/30 A man is wounded in Brussels Airport in Brussels 
 
 4/30 A man speaks on a mobile phone in Brussels Airport, after the explosions ripped through the departure hall 
 
 5/30 Belgian police officers detain a man at the Gare du Midi train station in Brussels 
 
 6/30 A police officer stands guard as people are evacuated from Brussels airport, after explosions rocked the facility in Brussels 
 
 7/30 People stand near Brussels airport after being evacuated following explosions that rocked the facility in Brussels 
 
 8/30 Crew and passengers are evacuated from Zaventem Bruxelles International Airport after an attack in Brussels 
 
 9/30 Passengers gather near Brussels airport in Zaventem, following its evacuation after blasts rocked the main terminal of Brussels airport 
 
 10/30 Two women wounded in Brussels Airport in Brussels 
 
 11/30 Passengers and airport staff are evacuated from the terminal building after explosions at Brussels Airport in Zaventem near Brussels 
 
 12/30 Passengers and airport staff are evacuated from the terminal building after explosions at Brussels Airport in Zaventem near Brussels 
 
 13/30 Broken windows seen at the scene of explosions at Zaventem airport near Brussels 
 
 14/30 People leave the scene of explosions at Zaventem airport near Brussels 
 
 15/30 People are evacuated from the scene after two explosions were heard at Brussels Airport 
 
 16/30 People wait outside of the Brussels Airport after evacuation 
 
 17/30 People leave the airport area after explosions at Brussels Airport in Zaventem 
 
 18/30 Passengers comfort each other as they are evacuated from the terminal building after explosions at Brussels Airport in Zaventem 
 
 19/30 People react as they walk away from Brussels airport after explosions rocked the facility in Brussels 
 
 20/30 Emergency services attend the scene of explosions at Zaventem airport near Brussels Reuters 
 
 21/30 Injured people at the scene at Brussels Airport after two explosions were heard PA 
 
 22/30 The aftermath of the explosions at Brussels airport PA 
 
 23/30 People wait outside of the Zaventem airport after two explosions were heard PA 
 
 24/30 Emergency services at the scene of explosions at Brussels Airport 
 
 25/30 A view of the scene after the explosions at Brussels airport PA 
 
 26/30 Emergency services at the scene of explosions at Zaventem airport near Brussels Reuters 
 
 27/30 The aftermath of the explosions at Brussels airport PA 
 
 28/30 The view of the Brussels airport after the explosion PA 
 
 29/30 Smoke is seen at Brussels airport in Brussels AP 
 
 30/30 A photo shows cars on a blocked highway near Zaventem, Brussels National airport, after two explosions rocked the main hall of Brussels Airport Getty Images 
 
 There are good reasons to believe that Abdeslam has been on the run from Isis for the last four months, as well as the Belgian and French police. He pulled out of a suicide bombing in Paris on 13 November. The network which has hidden him under the nose of the Belgian’s security services appears to have been composed mostly of disaffected youths with no particular Islamist axe to grind. 
 
 Yesterday’s attacks could have been carried out by a quite different 'cell', as a demonstration of continuing jihadist menace rather than specifically to “avenge” Abdeslam. 
 
 Video shows people fleeing Brussels airport explosion 
 
 All these facts point, nonetheless, to a deep and festering problem in Brussels, which goes beyond, the disturbing radicalisation of a fringe of Muslim youth in France or Britain or the Netherlands or Germany. Why Belgium? Why Brussels? Why Molenbeek? 
 
 There are the usual factors – unemployment, discrimination, split-identities – which explain the alienation of young Muslims in other European countries. In Belgium, they have been intensified by the country’s own divided identity as Dutch and French speakers have drifted further apart in the last two decades. Most Muslim youths in Britain or France do consider themselves British or French. What should a youth of Moroccan origin born in Brussels consider him or herself to be? A Fleming or a Walloon? Or a Bruxellois? 
 
 At the same time, the division of the country in all but name has undermined the national or federal institutions – including the police, justice system and intelligence services. Belgian politicians now think largely in terms of their “regions” or language communities, rather than problems on a national scale. The different branches of the police and security services have infamously poor communications with one another. Hans Bonte, the mayor of Vilvoorde, a suburban town outside Brussels, once called Belgium’s security arrangements “a perfect example of organised chaos.” 
 
 A country which regards itself as supremely international has become dysfunctionally preoccupied with parish politics. Add to this the fact that Belgium has long been a clearing house for illegal arms deals and that its geographical situation makes it a perfect launch-pad for attacks on neighbouring countries. 
 
 Until today, the hatred of western and democratic values spawned in Europe’s “capital” has mostly been exported. Divided, inward-looking Belgium is no longer immune.
– They are the two words headlining article after article: "Why Brussels?" The question isn't isolated to Tuesday's attacks, but a more overarching one reflective of Belgium's emergence as a European terror hub, though at the Independent, John Lichfield writes that until Tuesday, the country has been an "incubator of jihadism rather than itself a target." Some insights: Matthew Levitt, director of the Washington Institute's Stein Program on Counterterrorism and Intelligence, outlines four contributing factors to Business Insider: "They have the largest number per capita of western foreign fighters from any country." Intelligence agencies historically focused on EU spying, and the country's legal system doesn't exactly help. "It is a deeply divided government regionally, ethnically, linguistically," says Levitt. "There are multiple parliaments." That makes "communication across jurisdictions" problematic. Further, there are limitations on what type of surveillance police can legally carry out. A Belgian counterterror official put it plainly to BuzzFeed last week: "It's literally an impossible situation and, honestly, it’s very grave." As a small country—it's not quite as large as Maryland—"we just don’t have the people to watch anything else and, frankly, we don’t have the infrastructure to properly investigate or monitor hundreds of individuals suspected of terror links, as well as pursue the hundreds of open files and investigations we have." At the Independent, Lichfield writes the usual suspects are present (unemployment, discrimination), but they're exacerbated by Belgium's "own divided identity as Dutch and French speakers have drifted further apart in the last two decades. Most Muslim youths in Britain or France do consider themselves British or French." It's less clear-cut in Belgium, and the fractured nature extends to law enforcement and politics. "Add to this the fact that Belgium has long been a clearing house for illegal arms deals and that its geographical situation makes it a perfect launch-pad for attacks on neighboring countries."