MANILA >> A Philippine air force plane with 96 soldiers and crew members aboard crashed on the southern island of Jolo on Sunday, officials said. At least 45 people were killed, including three civilians on the ground, and it was feared that the toll would climb.

The head of the Philippine armed forces, Gen. Cirilito Sobejana, said that the plane missed a runway while trying to land and that it crashed near a village called Bangkal in the town of Patikul, a stronghold of the militant group known as Abu Sayyaf.

The military said that 42 who were on the plane had been confirmed dead, with another 49 injured and five others still unaccounted for.

“We remain to be hopeful that we could find more survivors,” Maj. Gen. William Gonzales, the Joint Task Force Sulu commander, said in a statement.

Military officials said that in addition to the three civilians on the ground who had been killed, 53 others had been injured.

The soldiers on the plane were being flown to Jolo to bolster the military’s operations against Abu Sayyaf, a small Islamist group that the Philippine government considers a terrorist organization.

“They were supposed to join us in our fight against terrorism,” Gonzales said. “These individuals were supposed to report to their battalions today.”

All passengers, pilots and crew members were retrieved, officials said, and the search for the aircraft’s “black box” was ongoing.

In addition to the 96 people aboard the plane, a C-130 Hercules, there were also five military vehicles, officials said. The C-130, a U.S.-built turboprop, is commonly used by militaries around the world and is sometimes kept in service for decades.

Defense Secretary Delfin Lorenzana said he had “ordered a full investigation to get to the bottom of the incident, as soon as the rescue and recovery operation is completed.”

The plane that crashed Sunday first flew in 1988, and it was used by the U.S. Air Force until it was sold to the Philippines in January, according to the Philippine air force and a website that tracks C-130s worldwide.

The Philippine military has been trying to modernize its aging fleet. Last month, a newly acquired Black Hawk helicopter crashed during a night training flight, killing six people onboard.

That crash happened about two months after another helicopter, an MG-520 attack chopper, crashed in the central Philippines, killing its pilot. And in January, a refurbished UH-1H Vietnam War-era helicopter crashed in the south, killing seven soldiers.

In 2008, a Philippine air force C-130 crashed into the sea shortly after taking off from Davao City on the southern island of Mindanao, killing nine crew members and two passengers aboard.

The Philippine military has been battling a stubborn insurgency in the southern part of the country for years.

A faction of Abu Sayyaf, which has pledged allegiance to the Islamic State group, was blamed for the January 2019 bombing of a cathedral on Jolo, which was carried out by an Indonesian couple and killed at least 23 people. Philippine authorities believe a similar attack near the cathedral in 2020, which left 14 dead, was perpetrated by the same Abu Sayyaf faction.

Its leader, Hatib Hajan Sawadjaan, is since thought to have been killed, and the military has been ramping up its operations against the group in hopes of eliminating it.

This article originally appeared in The New York Times.