Sri Lanka, Feb. 26 -- At least 18 people died and 23 were injured after a tour bus overturned and fell into a ditch in eastern Thailand on Wednesday.

The accident happened at 4am in the morning when the double-decker bus was descending at the Khao San Pu Tone mountain in Prachinburi province and the brakes failed, the police said.

The bus was carrying 49 passengers, including the driver, on an educational field trip.

"It was a downhill road and the brakes failed, and the driver lost control of the vehicle before it overturned," said Colonel Sophon Phramaneehe, adding that those who died were adults on a study trip.

Visuals of the accident showed a bus lying on its side in a ditch on the roadside as rescue and medical workers arrived a...