MANILA, Philippines (AP) — At least 17 people were killed when their passenger van collided with a cargo truck then burst into flames Monday in the southern Philippines, police said.

Three other people were injured by the midday collision in an accident-prone road in Antipas town in Cotabato province, Antipas police chief Capt. Godofredo Tupas II said.

The 10-wheel cargo truck, which was loaded with sand and gravel, was negotiating a downhill road when its brakes apparently malfunctioned and caused it to slam into the passenger van, Tupas said.

All but one of the 18 people onboard the van, including the driver, were killed by the impact and the flames, Tupas told The Associated Press by telephone.

Army troops, police and villagers extricated the victims from the van, many of them badly burned. Police took custody of the truck driver, who would be investigated before facing possible criminal complaints, Tupas said.

Deadly road accidents are common in the Philippines because of weak enforcement of traffic regulations, dilapidated vehicles and dangerous road conditions, including inadequate safety signs and barriers in mountain roads and far-flung provinces.