Failed military overthrow of President Corazon Aquino
On August 28, 1987, a coup d'état against the government of Philippine President Corazon Aquino was staged by members of the Armed Forces of the Philippines (AFP) belonging to the Reform the Armed Forces Movement (RAM) led by Colonel Gregorio Honasan, who had been a former top aide of ousted Defense Secretary Juan Ponce Enrile, one of the instigators of the People Power Revolution that brought Aquino to power in 1986. The coup was repelled by military forces loyal to Aquino within the day, although Honasan managed to escape.
The coup was the sixth such attempt to overthrow Aquino and marked her final break with RAM, whose mutiny against the regime of President Ferdinand Marcos helped propel her into office. It was also the deadliest instance of infighting within the Philippine military at the time until it was surpassed by a subsequent coup attempt in 1989, which was also launched by Honasan and RAM to overthrow Aquino.
Background.
The Reform the Armed Forces Movement (RAM) was a group of dissident soldiers and officers of the AFP that was formed in the latter years of the dictatorship of President Ferdinand Marcos. In 1986, some of these officers, led by Colonel Gringo Honasan and Defense Minister Juan Ponce Enrile launched a failed coup d'état against Marcos and were later joined by AFP Vice Chief of Staff Lieutenant-General Fidel Ramos, prompting a large number of civilians to attempt to prevent Marcos from wiping the RAM rebels out. This eventually snowballed into the People Power Revolution which ended the Marcos dictatorship and forced him into exile, replacing him with his electoral rival, Corazon Aquino.
However, RAM's relations with the new president gradually deteriorated, and the group was subsequently implicated in several coup attempts against her, one of which, the God Save the Queen Plot in November 1986, led to Enrile's dismissal as defense minister by Aquino, and the transfer of Honasan to Fort Magsaysay in Nueva Ecija, 200 kilometers north of Manila. Incidentally, the base was the largest military reservation of the AFP, making it a convenient pool of recruits for RAM's plot. 
Preparations for the coup.
In Fort Magsaysay, Honasan was tasked with heading the Philippine Army Special Forces training school there and personally managed the Philippine Army's 1st Scout Ranger Regiment. Within a few months, the charismatic Honasan had won over his students whose training as commandos with tactical mobility made them an ideal coup force. Honasan then held back his students' graduation from his courses as part of his efforts to train and indoctrinate them for the coup, which was not noticed by his superior officers for several months.
A few days before the coup, Major General Renato De Villa, chief of the Philippine Constabulary (PC), received an intelligence report that a coup would be launched by soldiers from Fort Magsaysay. He immediately relayed the information to General Ramos, now the AFP Chief of Staff, who quickly planned a pre-emptive counteraction. Ramos alerted the Philippine Army's 5th Division to verify the report, and ordered Brigadier General Ramon Montaño, his deputy chief of staff for operations, to accompany him to Fort Magsaysay early on August 28, 1987 to check the situation themselves.
Reasons for the coup.
Various statements broadcast by the rebels referred to "the overindulgence in politics which now pervades in society", the supposed mishandling of the communist insurgency, and the deplorable economic condition of the military rebels, as well as investigations by the Commission on Human Rights on the military as their reasons for launching the coup. Moreover, the situation coincided with rising discontent within the overall ranks of the AFP for the Aquino government, with a survey taken three months before the coup showing that 34% of officers agreed that "an incompetent civilian leader could justly be ousted by military men", versus 33% who disagreed.
Coup.
Advance on Manila.
Government attempts to intercept the rebels were preempted when, on the evening of August 27, Honasan and his trainees rode south on commandeered buses, dozens of 6X6 trucks and three tanks along the North Diversion Road towards Manila. Their classroom blackboards were later found to have contained maps with the presidential offices at Malacañang Palace and AFP headquarters at Camp Aguinaldo in Quezon City marked as targets. By midnight, they were joined by troops from other nearby military camps near the Santa Rita tollgate in Guiguinto, Bulacan, and flew inverted Philippine flags symbolizing war. General Ramos subsequently said that the rebels to aimed "to kill the President and her family," which was further highlighted by an intercepted radio message discovered by the Integrated National Police on August 27 mentioning Aquino's assassination by the end of the month.
In the early morning of August 28, the rebel convoy was spotted by government forces in Santa Maria, Bulacan, with an estimated strength of more than 2,000, all of them heavily armed. Upon hearing of the convoy's sighting, General Montaño concluded that the rebels would attack in half an hour. In response, the head of the Philippine Army, Major General Restituto Padilla Sr., immediately dispatched five tanks to reinforce Camp Aguinaldo. The convoy arrived in Manila at around 1:00 am.
Malacañang.
RAM marked their arrival in Manila by firing their guns into the air, waking up many residents of the capital and alerting government forces to their whereabouts. Honasan led one column on a night attack on Malacañang while leaving two deputies to lead attacks on Philippine Air Force headquarters at Villamor Air Base in Pasay and several television stations.
At 1:45 am, Honasan ordered 200 of his men and several V-150 armored vehicles to advance down Jose Laurel Street towards the palace. Despite reaching Malacañang's gates, his forces were beaten back by the Presidential Security Group led by Colonel Voltaire Gazmin, who were reinforced by the Philippine Marines commanded by Brigadier General Rodolfo Biazon, forcing them to retreat into nearby roads. Fifteen minutes later, Colonel Reynaldo Ochosa led his 62nd Infantry Battalion to assault the nearby Nagtahan Bridge, only to be repulsed by loyalist soldiers. He was followed by the 14th IB under Lieutenant Colonel Melchor Acosta Jr., who retreated after another round of government fire. At this time, the rebels ambushed a car carrying Aquino's son Noynoy as he was returning to the palace, wounding him and killing three of his companions. He sustained injuries from five bullets, one of which remained lodged in his neck for the rest of his life. Two palace sentries were also reported to have been shot.
Realizing that his assault had failed, Honasan ordered his men to regroup at Camp Aguinaldo. Near Nagtahan Bridge, they were met by unarmed civilians supporting the president who jeered at them. The rebels opened fire on the crowd with automatic weapons, killing eleven people, ten of whom were minors, and injuring 54.
Aquino, who resided at the nearby Arlegui Guest House, was woken up at 1:30 am by the gunfire and was asked by one of her daughters what was happening. After her duty officer went out to inspect the situation, she made futile calls to Ramos, who was on this way to Camp Aguinaldo at that time, and her Executive Secretary, Joker Arroyo, before deciding to wait the fighting out by praying the rosary with her daughter. At 4:45 a.m. she went on the air to announce that the attack on Malacañang had been repulsed and that she was safe and well. She urged people to stay indoors until the rebellion was quelled and suspended classes in Metro Manila as well as her scheduled trip to Central Luzon that day. Listeners recalled her voice being reassuring, unhurried and unemotional.
Camp Aguinaldo.
An advance rebel party tried to enter Gate 1 of Camp Aguinaldo but were initially held off by a squad led by Colonel Emiliano Templo and backed by armored vehicles. They were later able to gain entry and were followed by Honasan and his forces from Malacañang. Honasan himself led his men in seizing parts of the camp, including the headquarters of the Department of National Defense.
Despite the rebel presence just 100 meters away, the building housing the AFP General Headquarters was still held by loyal soldiers led by Montaño, AFP Vice Chief of Staff Lieutenant General Eduardo Ermita, and deputy chief of staff for civil military operations Brigadier General Orlando Antonio. Finding that the rebels had failed to cut off phone lines, Ramos, who had set up camp at the adjacent headquarters of the Philippine Constabulary in Camp Crame ordered the officers to defend the four-story GHQ building despite being surrounded by the rebels. During the subsequent fighting, the right wing of the building caught fire after the rebels entered the premises and poured gasoline, forcing the trapped officers to "crawl towards the left side of the building" to avoid the flames and snipers.
Around noon, Ramos ordered Marine reinforcements to open fire at rebel positions with artillery and assault the camp, leading to heavy fighting within and around the camp that lasted until 4 pm. They were later joined by vintage T-28 aircraft from Sangley Point Air Station in Cavite who strafed rebel positions in the camp and bombed the west wing of the GHQ building, further contributing to the existing fire.
Villamor Air Base.
At 2:30 am, Philippine Air Force vice commander Brigadier General Federico Pasion, a secret rebel sympathizer, ordered his men to occupy the PAF headquarters building at Villamor Air Base. They succeeded in taking control of the first and second floors, while his superior, Major General Antonio Sotelo, an Aquino loyalist, held his ground at his office on the third floor despite pleas by his son, who had been captured by the rebels. The rebels also seized some of the gates, the motor pool and helicopter storage areas, and were later met by a column sent by Honasan.
At daybreak, Aquino loyalist and Commander of the 205th Tactical Helicopter Wing Brigadier General Loven Abadia managed to enter the base and led government soldiers in a firefight with the rebels during which they were able to retake some helicopters and fly them to Fort Bonifacio along with Sotelo, who escaped through a fire exit and stumbled upon a heavily armed Pasion, whom he managed to disarm. In the late afternoon, the rebels withdrew from the base while rebel reinforcements from Bicol turned back upon hearing news of the coup's failure.
Media outlets.
The rebels seized four television stations in Quezon City, namely ABS-CBN, PTV-4, RPN-9 and IBC-13, and used the channels to broadcast propaganda. Heavy fighting later led to the closure of those stations, leaving only one pro-government channel on-air to broadcast demands for the rebels to surrender.
Brigadier General Alfredo Lim, commander of the Metropolitan Police Force's Western Police District was ordered to retake the ABS-CBN compound which housed both the station and PTV-4 and where loyalist holdouts were besieged by the rebels, as well as Broadcast City, which housed both IBC and RPN. Arriving in the area around noon, Lim and his men encountered some of the first rebel surrenderees who said they were tired of waiting for more than 12 hours for orders. Lim then launched an assault on rebel positions in the compound and on the adjacent Camelot Hotel, supported by the T-28 fighters from Camp Aguinaldo, which left one policeman killed and two wounded. The assault lasted until 2 pm when the rebels surrendered.
Provinces.
Back in Fort Magsaysay, a unit led by Major Horacio Lactao broke out of the camp in the morning of August 28 to join RAM forces in Manila. However, upon realizing that the coup had failed, Lactao decided to turn back, arriving in camp the following day.
In Pampanga, rebels led by PC officers Colonel Reynaldo Berroya and Major Manuel Divina seized Camp Olivas in San Fernando, which Aquino was supposed to visit on August 28, and captured the PC regional commander for Central Luzon Brigadier General Eduardo Taduran, along with his six senior staff officers. Other rebel units managed to capture Basa Air Base, home of the PAF’s fighter planes, in Floridablanca, Shortly before midnight the rebels withdrew from their positions. 
In Albay, 80 rebel soldiers led by PC officers Ludovico Dioneda, Diosdado Balleros and Reynaldo Rafal seized Legazpi Airport. Four truckloads of soldiers went to Manila to support the rebels, only to turn back upon learning the coup had failed. After waiting in vain for a promised transport plane to ferry