HANOI, December 8 (RIA Novosti) - At least eight miners were killed and another 20 injured in a methane explosion in a coalmine in northeastern Vietnam early on Monday, local media reported.

The blast occurred in the Quang Ninh Province, Vietnam's main coal mining region, while 116 miners were working 250-meters (820-feet) underground, media reports said.

The remaining miners, who were underground at the time, managed to escape the blast, media reported.

An investigation is being conducted to find the cause of the explosion.