Nineteen farmers were killed in the mountainous northern Philippines when a truck carrying them and sacks of rice seeds plunged backwards down a deep ravine, police said Friday.

The victims were on their way home from collecting government subsidised seeds late Thursday in the town of Connor when the driver lost control of the vehicle, in the latest tragedy on the country's perilous roads.

Either the engine or brakes failed as the truck made its way up an incline. The vehicle, with some 40 people in its bed, then plunged back down the hill into a 20-metre (65-foot) ravine.

"The truck fell on its rear first and the passengers were crushed," local police official Manuel Canipas told AFP.

He added another 20 more people on the truck were injured, but will survive.

Canipas said the weight of the seeds may have made the crash worse, potentially crushing some of the victims. 

Deadly road accidents are common in the Philippines, where inadequately maintained buses and poorly trained drivers form the backbone of land transport options.

Twenty people, including children, were killed in September in the southern Philippine town of T'boli when a truck carrying a group home from a party at the beach crashed.

© AFP