The collision took place this morning at a railway crossing in Heihe City of Heilongjiang province, state-run Xinhua news agency reported.
The accident happened when a supervisor in charge of the railway crossing failed to reach the area in time to warn vehicles of the approaching train at a railway crossing in Heihe City, a senior railway official in Heihe told Xinhua.
All the victims were passengers on the bus, which belonged to a local public transport company while the train, operated by a local railway company in Heihe, has left the scene.
The railway line resumed operation, the report said.