Jakarta. Two light attack aircraft, each carrying a pilot and a co-pilot, crashed in the East Java town of Pasuruan just before noon on Thursday. The fate of the personnel onboard remains unknown pending the evacuation process.

Residents living on the slope of Mt. Bromo in Pasuruan, East Java, reported witnessing flaming aircraft wreckage after hearing explosions.

A statement from the Indonesian Air Force identified the aircraft involved in the incident as two EMB-314 Super Tucanos bearing tail numbers TT-3111 and TT-3103.

The two planes departed from the Abdulrachman Saleh Air Base in Malang, East Java, for a training mission alongside two similar aircraft at 10:50 a.m. local time (3:50 GMT), the statement read.

At 11:18, air control lost contact with the two aircraft, while the remaining two Tucanos safely returned to the base at 11:31.

Before the incident occurred, the four planes were reported to have flown in a “box formation” and reached an altitude of 8,000 feet.

The individuals onboard the ill-fated aircraft were identified as Lie. Col. Sandhra Gunawan (TT-3111, front seater), Col. Widiono (TT-3111, back seater), Major Yuda A. Seta (TT-3103, front seater), and Col. Subhan (TT-3103, back seater).