NANCHANG - Three people are trapped underground after a coal mine flooded in east China's Jiangxi Province, local authorities said Monday.

The accident happened at about 3 am Sunday at Baoshan Coal Mine in Leping City while workers were performing technological upgrading, according to the provincial coal mine safety administration.

The administration sent experts to guide the rescue on Monday.

Rescue is under way at the scene. The cause of the accident is being investigated.