Eleven people, including two children, burned to death in a passenger van crash in Korat on Saturday night, police confirmed Monday.

The van carrying 12 people was travelling from northeastern Amnat Charoen province to Bangkok when it veered off the highway in central Nakhon Ratchasima province Saturday night, police said.

Police told AFP that one man had been able to climb out a window, but the other passengers were trapped and died in the blaze.

The survivor, Thanachit Kingkaew, a 20-year-old student, said he was asleep when he was jolted awake after hearing someone scream.

"I woke up and the next thing I know, the van was upside down. I didn't see what happened," he said.

"After the crash, the fire started engulfing the whole van starting from the back."

"I started kicking the windows and managed to crawl through a small hole," he said.

"Soon after that, the van exploded."

A volunteer with a local rescue team said the van exploded just seconds after it was engulfed in flames.

"It took less than 30 seconds for the fire to consume the whole van," he said.

"I couldn't do anything with the fire extinguisher I had. The van then exploded three to four times."

Police were still investigating what caused the vehicle to veer off the road.