The mine was flooded resulting in the deaths of the miners. One body was retrieved and four others still trapped, state-run Xinhua news agency reported.
An initial investigation showed that water from an abandoned mined-out area above the mining platform, where the accident occurred, was to blame for the tragedy.
The accident happened yesterday a shaft of the Junyuan coal mine in Xing'an district of the resource-rich city of Hegang when 28 miners were working in the pit.
Fourteen of the miners managed to escape or have been rescued, an official with the local safety administration said. The coal mine is licensed, according to the Hegang city government.