Updated July 5, 2021 at 8:02 AM ET

MANILA, Philippines — Philippine troops found the last five dead from the crash of a transport aircraft in the south, raising the death toll to 50 in the military's worst air disaster, officials said Monday.

The Lockheed C-130 Hercules was carrying 96 mostly combat troops when it overshot the runway while landing Sunday at the Jolo airport in Sulu province, military officials said. It slammed into a coconut grove beyond the airport and burst into flames in a disaster witnessed by horrified soldiers and villagers.

Troops, police and firefighters rescued 49 military personnel, including a few who jumped off the aircraft before it exploded and was gutted by fire. Seven people on the ground were hit by aircraft parts and debris and three of them died, the military said.

The plane was one of two refurbished U.S. Air Force aircraft handed over to the Philippines, Washington's oldest treaty ally in Asia, as part of military assistance this year.

The aircraft earlier had carried two-star Gen. Romeo Brawner Jr., his wife and three children from Manila to southern Cagayan de Oro city, where he became the new military regional commander on Monday.

Brawner was stunned to learn the plane he'd just flown on had crashed. "We're very thankful that we were spared, but extremely sad that so many lost their lives," Brawner told The Associated Press.

Those who boarded the C-130 in Cagayan de Oro for the flight to Sulu were army troops, many of them newly trained recruits, to be deployed in the battle against Abu Sayyaf militants in the south.

"They were supposed to join us in our fight against terrorism," Sulu military commander Maj. Gen. William Gonzales said. Government forces have been battling Abu Sayyaf militants in the predominantly Muslim province of Sulu for decades.

A video taken by troops showed the aircraft landing in clear weather and then vanishing beyond the airport. "It vanished, it vanished," one soldier exclaims. Dark gray smoke later billowed from the crash site in a wooded area as the troops yelled "It fell, it fell!" in horror.

It was not immediately clear what caused the crash and investigators were looking for the C-130's cockpit voice and flight data recorders. At least one other C-130 was grounded while investigators determine the cause of the crash, military officials said, adding that smaller aircraft would be used for routine missions including the transport of COVID-19 vaccines and medical supplies across the archipelago.

Regional military commander Lt. Gen. Corleto Vinluan said it was unlikely that the aircraft took hostile fire. Military chief of staff Gen. Cirilito Sobejana told reporters Sunday that "the plane missed the runway and it was trying to regain power but failed and crashed."

An air force official told the AP that the Jolo runway is shorter than most others in the country, making it more difficult for pilots to adjust if an aircraft misses the landing spot. The official, who has flown military aircraft to and from Jolo several times, spoke on condition of anonymity because of a lack of authority to speak publicly.

President Rodrigo Duterte expanded the military presence in Sulu to a full division in late 2018, deploying hundreds of additional troops, air force aircraft and other combat equipment after vowing to wipe out the Abu Sayyaf. The small but brutal group has been listed by the U.S. and the Philippines as a terrorist organization because of ransom kidnappings, bombings and beheadings.

Before Sunday, the Philippine air force's deadliest disaster was a crash in a rice field north of Manila in 1971 that killed 40 military personnel, military historian Jose Custodio said.

A recently delivered S-701 Blackhawk helicopter crashed more than a week ago near Clark freeport, a former U.S. air base, killing all six air force personnel on board.

The government has struggled for years to modernize its military, one of Asia's least equipped, as it deals with decades-long Muslim and communist insurgencies and territorial rifts with China and other claimant countries in the South China Sea.

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