Abdelhamid Abaaoud, the suspected mastermind behind the Paris attacks, died during a major police raid in a northern suburb of the French capital. 
 
 Officials confirmed Abaaoud was the target of the operation that developed into a siege in St Denis on Wednesday, as more details emerged about the man thought to have arranged the shootings which killed 129 people on Friday night. 
 
 Now a prominent member of Isis, Abaaoud first travelled to Syria last year - but seemingly not out of any great religious motivation. 
 
 "He did not even go to the mosque,” his older sister Yasmina told the New York Times earlier this year. 
 
 Like many who travel to the so-called “Islamic State”, his actions appear to have been motivated more by a thirst for power, violence and unaccountability. 
 
 Who was Abdelhamid Abaaoud, mastermind of the Paris attacks? 
 
 Abaaoud, in his late 20s, was born in Belgium and grew up in the Brussels suburb of Molenbeek, which has become a key focus for investigators in recent days. 
 
 He briefly studied at an exclusive Catholic school, before either dropping out or getting expelled and drifting into a life of thievery and drugs. 
 
 Abdelhamid Abaaoud boasted of his escape from authorities in Belgium following a failed terrorist attack in an interview published in Isis' propaganda magazine in February 
 
 According to his family, the young man showed much more interest in petty crime than Islam, and they were shocked when he took his 13-year-old brother Younes with him to travel to Syria in January 2014. 
 
 After he was trained and further radicalised in Syria, Abaaoud was able to return to Europe via Athens. He was picked up by European security services and reportedly even stopped by police but let go, after which he disappeared. 
 
 Officials identified the suspected mastermind as Abaaoud, a Belgian of Moroccan origin in his late twenties 
 
 In February, he gave an interview to the Islamic State English-language magazine Dabiq which suggested he was in Syria. 
 
 In the interview he claimed he had travelled to Belgium to "terrorise the crusaders waging war against the Muslims". 
 
 He also claimed a police officer who stopped him had failed to recognise him even after his picture had been sold to the media. 
 
 In pictures: Saint-Denis raid 
 
 
 
 
 
 
 
 33 show all In pictures: Saint-Denis raid 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 1/33 A man is arrested by police officers at the site where a raid happened in the city center of Saint-Denis, near Paris 
 
 2/33 Hooded police officers detain a man in Saint-Denis, near Paris 
 
 3/33 Hooded police officers detain a man in Saint-Denis, near Paris 
 
 4/33 Police officers detain a man on the ground inside a shopping mall in Saint-Denis 
 
 5/33 Police officers arrest a man in Saint-Denis, a northern suburb of Paris 
 
 6/33 French police officers storm a church after a raid in Paris suburb Saint-Denis 
 
 7/33 Police officers at work at the site where a raid happened in the city center of Saint-Denis 
 
 8/33 Some people are being transferred to a local hospital near the site of this morning police raid in Saint-Denis 
 
 9/33 Residents are evacuated in Saint-Denis 
 
 10/33 Inhabitants are evacuated from a security perimeter set in the northern Paris suburb of Saint-Denis city center 
 
 11/33 Families are evacuated by police members at the site were a police raid happened in the city center of Saint-Denis 
 
 12/33 Rescue teams take care of an injured police officer at the site where a police raid happened in the city center of Saint-Denis 
 
 13/33 Members of special French RAID forces with a police dog and French riot police (CRS) secure the area during an operation in Saint-Denis 
 
 14/33 Police forces operate in Saint-Denis, a northern suburb of Paris 
 
 15/33 French riot police (CRS), soldiers, firefighters and health workers stand at the scene in Saint-Denis 
 
 16/33 French riot police (CRS) secure the area as shots are exchanged in Saint-Denis Reuters 
 
 17/33 Rescue teams and police gather at the site where raid happened in the city center of Saint-Denis 
 
 18/33 Soldiers operate in Saint-Denis, a northern suburb of Paris AP 
 
 19/33 Police officers take up positions in Saint-Denis, a northern suburb of Paris AP 
 
 20/33 Police and Ambulance vans are parked in Saint-Denis, a northern suburb of Paris AP 
 
 21/33 A resident is being searched by police officers in Paris suburb Saint-Denis AP 
 
 22/33 Members of French police special forces in the northern Paris suburb of Saint-Denis city center, as French Police special forces raid an appartment, hunting those behind the attacks that claimed 129 lives in the French capital 
 
 23/33 Anti-terrorist police raid apartment in Saint Denis, Paris. Reports suggest the target of the police siege in Saint-Denis is Abdelhamid Abaaoud, thought to be the mastermind behind the Paris attacks. Three suspected terrorists have barricaded themselves in an apartment gunfire has been exchanged between the men and dozens of armed police Rex 
 
 24/33 French special police forces secure the area as shots are exchanged in Saint-Denis Reuters 
 
 25/33 French police evacuate residents in Saint-Denis Reuters 
 
 26/33 Police officers take up positions in Saint-Denis, a northern suburb of Paris AP 
 
 27/33 Police forces prepare in Saint-Denis, a northern suburb of Paris AP 
 
 28/33 French spolice stop and search a local resident as shots are exchanged in Saint-Denis 
 
 29/33 French police members participate in an raid in the city center of Saint-Denis EPA 
 
 30/33 French special police forces secure the area as shots are exchanged in Saint-Denis Reuters 
 
 31/33 Firemen wait for the develop of the operation in the city center of Saint-Denis EPA 
 
 32/33 French police secure the area as shots are exchanged in Saint-Denis Reuters 
 
 33/33 French special police forces secure the area as shots are exchanged in Saint-Denis Reuters 
 
 He said: "I was even stopped by an officer who contemplated me so as to compare me to the picture, but he let me go, as he did not see the resemblance!" 
 
 Abaaoud claimed he was able to travel “safely” back to Syria when it suited him. He said: “I was able to leave and come to Sham (Syria) despite being chased by so many intelligence agencies. 
 
 “All this proves that a Muslim should not fear the bloated image of the crusader intelligence. My name and picture were all over the news yet I was able to stay in their homeland, plan operations against them, and leave safely when doing so became necessary.” 
 
 Abaaoud is believed to have had links to previous foiled terror attacks in France, including one on a Paris-bound high-speed train that was thwarted when passengers overpowered a gunman in August. He was thought to have been involved in the attack remotely from Syria – a theory thrown into doubt by this week’s developments. 

 At about the time Mr. Abaaoud began his return journey to Europe, Abu Muhammad al-Adnani, a leader with the Islamic State — he now has a $5 million bounty on his head, offered by the United States — made an impassioned plea for the killings of disbelievers. “If you can kill a disbelieving American or European, especially the spiteful and filthy French, then rely on Allah and kill him in any manner or way however it may be,” Mr. Adnani said in a recorded message. 
 
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 Western intelligence agencies, worried that the Islamic State was planning to widen its carnage from the Middle East to Europe, tried to track a slow but steady trickle of fighters in Syria as they headed home to the Continent. 
 
 A Belgian television station reported Monday that security services had been alerted to Mr. Abaaoud’s return to Europe by a telephone call he made from Greece to an inmate, the brother of a known jihadist, in Belgium. 
 
 The realization among security officials that Mr. Abaaoud was back in Europe led to a major operation to intercept him. A safe house for militants he had helped set up in eastern Belgium was raided in January. 
 
 There, two of his comrades, including the brother of the inmate he had called, were killed. The Belgian authorities trumpeted the raid as having thwarted “a major terrorist operation.” 
 
 But it missed its principal target, Mr. Abaaoud, who then somehow made his way back to Syria, which Islamic State refers to by its historical Muslim name, “Sham.” 
 
 “Allah blinded their vision and I was able to leave and come to Sham despite being chased by so many intelligence agencies,” he later told Dabiq, a slickly produced magazine published by the Islamic State. 
 
 It is not known whether Mr. Abaaoud had any direct contact in Syria with Mr. Adnani, the architect of what the C.I.A. director, John O. Brennan, on Monday called the Islamic State’s “external operations agenda.” As a low-level fighter, Mr. Abaaoud was unlikely to have mixed with senior figures in the militant group’s hierarchy, experts in Belgium said. 
 
 But the two men shared a passion for propaganda, with Mr. Adnani serving as the Islamic State’s official spokesman and Mr. Abaaoud featured in various recruitment campaigns. 
 
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 Mr. Abaaoud also had an invaluable asset for Islamic State leaders eager to take their battle to Europe — a pool of friends and contacts back home willing to carry out attacks. 
 
 Like many of the jihadists who have carried out attacks in Europe, including the brothers who attacked the French satirical magazine Charlie Hebdo in January, Mr. Abaaoud showed far more interest in thievery and drugs when he was a young man than in Islam, particularly the highly disciplined, self-sacrificing Salafi strain favored by many militants. 
 
 Nor was his family impoverished. His father, Omar, owned a clothing store off the market square in Molenbeek, a borough of Brussels, and the family lived nearby in a spacious if shabby corner home on Rue de l’Avenir — Future Street — near the local police station. 
 
 Despite his subsequent denunciations of the mistreatment suffered by Muslims in Europe, he enjoyed privileges available to few immigrants, including admission to an exclusive Catholic school, Collège Saint-Pierre d’Uccle, in an upscale residential district of Brussels. 
 
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 He was given a place as a first-year student in the secondary school but stayed only one year. An assistant to Saint-Pierre’s director, who declined to give her name, said he had apparently flunked out. Others say he was dismissed for poor behavior. 
 
 He then drifted into a group of friends in Molenbeek who engaged in various petty crimes. Among his friends were Ibrahim and Salah Abdeslam, two brothers who, like Mr. Abaaoud, lived just a few blocks away and are now at the center of the investigation into the Paris attacks. 
 
 Ibrahim Abdeslam was one of the suicide bombers on Friday, and Salah Abdeslam, who rented a car in Brussels that was used to transport some of the gunmen in the attacks on Paris, is the target of an extensive manhunt. 
 
 Mr. Abaaoud was arrested for petty crime in 2010 and spent time in the same prison in Brussels where Ibrahim Abdeslam was being held, according to the spokesman for Belgium’s federal prosecutor and Ibrahim’s former lawyer. It is not known if they were in touch while in the prison, but they did not stay long. After their release, they returned to Molenbeek, often hanging out at a dingy bar known as a hangout for drug dealers. 
 
 To the dismay of his family, which had not seen him show any religious zeal, Mr. Abaaoud suddenly moved to Syria in the beginning of 2014, according to jihadi experts tracking Belgian militants. 
 
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 Soon after his arrival in Syria, where he stayed for a time in a grand villa in Aleppo used to house French-speaking jihadists, he explained his choice in a video: “All my life I have seen the blood of Muslims flow. I pray that God breaks the backs of those who oppose him” and “that he exterminates them,” he said. 
 
 Early this year, the French magazine Paris Match found a film that showed Mr. Abaaoud grinning and making jokes as he dragged corpses with a pickup truck. 
 
 “I suddenly saw my picture all over the media,” he told Dabiq. He added that “thanks to Allah, the infidels were blinded by Allah” and did not spot him when he returned to Europe at the end of last year. 
 
 He also somehow persuaded his younger brother, Younes, who was still in Molenbeek and only 13, to join him in Syria. The boy left Belgium for Syria on his own without raising any suspicion from the authorities. 
 
 Mr. Abaaoud’s father joined a state prosecutor’s case against his son in May for having recruited Younes. 
 
 “I can’t take it anymore,” Omar Abaaoud told local reporters at the time. “I am on medication,” he said, adding that his son had dishonored the family. “He destroyed our families. I don’t ever want to see him again.” 
 
 His father is now living in Morocco and wants to put the property on Future Street up for sale, a family friend said. 
 
 Now, Mr. Abaaoud is suspected of being a leader of a branch of the Islamic State in Syria called Katibat al-Battar al Libi, which has its origins in Libya. This particular branch has attracted many Belgian fighters because of language and cultural ties, said Pieter van Ostaeyen, who tracks Belgian militants. 
 
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 Many Belgian Muslims are of Moroccan origin, he said, and speak a dialect found in eastern Morocco that is similar to a Libyan dialect. Aymenn Jawad al-Tamimi, who studies jihadi groups at the Middle East Forum, a research center in Washington, said there was no evidence yet that the Paris attacks had been ordered by Mr. Adnani or the Islamic State’s overall leader, Abu Bakr al-Baghdadi. 
 
 But he added that the soldiers at the Libyan branch that includes Mr. Abaaoud had played a prominent role in exporting violence. One of their tasks, he said, has been to organize plots that “involved foreign fighters, sleeper cells in Europe that were connected with an operative inside of Syria and Iraq, usually in a lower to midlevel position.” 
 
 About 520 Belgian fighters have gone to Syria or Iraq to fight, making Belgium the biggest suspected source, per capita, of foreign fighters for ISIS. According to posts on Twitter and other social media accounts, the two men who were killed during the raid in Verviers, Belgium, in January were members of Katibat al-Battar.
– When the alleged mastermind of the Paris terror attacks was thought to have been killed in Syria a year ago while fighting for ISIS, his family prayed that it was true. Abdelhamid Abaaoud—who attended an exclusive Catholic school in Brussels before dropping out of secondary school and spending time in jail for petty crime—suddenly moved to Syria in 2014, reports the New York Times. He stayed for a time with French-speaking jihadists and soon after convinced his 13-year-old brother, Younes, to join him. "All my life I have seen the blood of Muslims flow. I pray that God breaks the backs of those who oppose him" and "that he exterminates them," he said in a video. "[Abdelhamid] destroyed our families," his father said at the time. "I don't ever want to see him again." Of course, Abaaoud, 26, was very much alive. His cellphone was tracked to Athens at the end of last year, an official says. It appears he then continued on to Belgium. A January raid on a safe house for militants there was meant to stop him, but Abaaoud again slipped through the cracks. "I was able to stay in their homeland, plan operations against them, and leave safely when doing so became necessary," he told an ISIS magazine, per the Independent. Now a suspected leader of ISIS branch Katibat al-Battar al Libi, which has recruited many Belgians, Abaaoud has likely proved valuable because of his connections, reports the Times. Among his childhood friends are Salah Abdeslam and his brother Ibrahim, a Paris suicide bomber. Authorities were said to be targeting Abaaoud during a raid north of Paris early Wednesday, but it isn't clear if he's been found.