The Philippine military yesterday began the painstaking task of investigating the deadliest plane crash in its history, as the death toll from the incident climbed to 52 and amid reports that the survivors had to jump out of the aircraft just before it hit the ground and broke up in flames.
"We are determined to find out what really transpired... We will determine what caused it... We are going to do that to ensure that incidents like this will not happen again," Major-General Edgard Arevalo, the military spokesman, told reporters.
The Lockheed C-130 military transport plane crashed at around noon on Sunday as it tried to land on a short runway in Patikul town in Sulu province, a stronghold of Muslim militants more than 900km south of the Philippine capital Manila.
A video taken at the site suggested that the pilots had tried to abort the landing but, for some reason, failed to pull up and instead the plane crashed near a hamlet that straddles the runway.
The plane was carrying 96 soldiers, including three pilots.
Forty-nine of the soldiers, most of them privates fresh from a six-month training course, died, according to the military's final casualty count. Three civilians who were on the ground and in the plane's path were also killed.
Witnesses said they saw people jumping out of the aircraft before it hit the ground.
Maj-Gen Arevalo declined to say if the wounds of those who survived were consistent with them having jumped from a fast-moving aircraft. "That information is not available to me yet," he said.
President Rodrigo Duterte flew to Zamboanga city, east of Sulu, where the bodies of some of those who had died were airlifted to. He conferred honours on six of them, leaving medals on top of caskets draped with the Philippine flag.
"I commiserate with you, and I am as sorrowful as you (are). As your commander-in-chief, I'm the one most hurt… The life of a soldier is always valuable, whether in the field, fighting or (unfortunate) events such as this," he said.
He added: "The most important thing is that they did not die in vain. They died for our country."
The C-130 is an American-built turboprop aircraft that is commonly used by militaries around the world, and is sometimes kept in service for decades. The Philippine Air Force has four of these planes, including the one that crashed.
The C-130 that crashed "was in tip-top shape", said Maj-Gen Arevalo. "It's not brand new, but in very good condition."
He added that the aircraft had 11,000 flight hours remaining when the United States turned it over to the Philippines in January.
All three pilots were "seasoned and experienced in flying this kind of aircraft", he said, and the plane "followed specific protocol regarding approach speed, landing spot and part of the runway where it landed".
"What has yet to be determined is what caused the aircraft to exceed the runway."
Investigators were already searching for the plane's flight data recorder and cockpit voice recorder, Maj-Gen Arevalo said, adding that accounts from eyewitnesses and data from the control tower were also being gathered.
He said the crash site had been secured so that militants in the area would not be able to hamper the investigation.
The kidnap-for-ransom outfit Abu Sayyaf is known to operate in Patikul.
Maj-Gen Arevalo also sought to douse speculation that the runway and airport were "accidents waiting to happen", or that the plane, with close to 100 soldiers and five vehicles on board, was too heavy.
"We appeal to the public to avoid speculation or unverified news. At this point, we have to wait for the result of the investigation," he said.
The Philippines has been modernising its air force to deal with threats from terrorists at home and challenges posed by China in disputed waters. But its armed forces have a patchy air safety record.
Last month, a newly acquired Black Hawk helicopter crashed during a training flight. Six people died in the incident.