At least six people were killed and many others injured after a bus carrying around 50 passengers fell off a bridge in Jharkhand's Hazaribag district on Saturday, police said.

The accident took place when the Ranchi-bound bus coming from Giridih district broke the railing of a bridge and fell into a dry spot in Siwanne River in Tatijharia Police Station area, Superintendent of Police Manoj Ratan Chothe said.

Rescue operation is underway as some passengers are still trapped in the bus, he said."Two passengers died on the spot, while four others were declared dead by doctors at Sadar Hospital in Hazaribag. The fatality figures may go up as some are seriously injured. We are preparing to send them to Rajendra Institute of Medical Science (RIMS) in Ranchi for better treatment," he said.

Damage could have been more had the bus fallen into water in the middle of the river, the officer said."Some passengers are still stuck in the bus and we are trying to rescue them by making an exit point with the help of gas cutters," he said.

A DSP-rank officer and three police station in-charge have been deputed to the spot to monitor the rescue operation, the SP added.