Nineteen people were killed after a double decker bus collided with a truck in central Thailand, reports say.

The passenger bus, traveling from Bangkok to Roi Et, caught fire after an 18-wheeler truck crashed into it early Tuesday on a highway in the Kaeng Koi district of Saraburi province.

The lorry reportedly ran across the traffic island and slammed into the bus, leaving at least 20 more hurt.

A pick-up truck behind the bus was also reportedly involved in the collision.

It was not immediately clear how many people were on board the bus. All of those who died were on the bus, Thai newspaper the Nation said.

Police said they have arrested the driver of the truck, reports AFP.

“The truck crossed from the opposite lane of traffic and hit the bus,” said local police officer Lieutenant Colonel Assavathep Janthanari.

An overnight sleeper train from Bangkok to the northern city of Chiang Mai came off the tracks earlier this month, injuring 23 people, including 18 foreign tourists, in another incident underlining the country’s poor safety transportation standards.