Police say at least four people have been killed and several injured in a head-on collision between a bus and a truck in southern Serbia.

The crash happened early Tuesday near the town of Kursumlija. Police say the bus veered directly into the path of the truck on a local road.

State TV says the bus carrying eight passengers caught fire after the accident. Three charred bodies were found inside the bus while the fourth victim is believed to be the truck driver.

Police are investigating the cause of the crash.