At least 33 people were killed and 30 injured when a train crashed into a bus in northwestern Sri Lanka on Wednesday.

The Colombo-bound bus tried to beat an express train at a crossing near Polgahawela, 80 km northeast of Colombo, the police said.

"We estimate at least 30 bus passengers were killed," a police spokesman said, adding the bus caught fire.

Rescue workers were still trying to get at the charred remains of passengers.

There were no immediate reports of casualties among the train passengers.