While three persons died on the spot, six persons succumbed to injuries at Bardhaman Medical College and Hospital, Superintendent of Police Syed Mohammad H Mirza said.
The accident occurred when the driver lost control over the vehicle on Natunhaat (near Katwa)- Benachiti (Durgapur) route and the bus overturned near Dhorola More in Panagarh, he said.
Fifty injured passengers were taken to Mankad Rural Hospital from where 45 were shifted to Bardhaman Medical College and Hospital.