The mishap occurred when the driver lost control over the speeding bus that overturned and fell into the roadside ditch filled with water, Superintendent of Police Varun Kumar Sinha said.
While two occupants of the bus were killed, 17 others sustained injuries, he said.
The injured were admitted to Mohiuddinagar sub-division hospital.
Efforts were on ascertain the identity of the victims, Sinha said.