The death toll from fierce storms and torrential rains battering southern China has risen to at least 70 people with tens of thousands left homeless, state media reported Sunday.

The extreme weather was unleashed on Wednesday, toppling thousands of homes and destroying crops across vast swathes of agricultural land, the Xinhua news agency said, warning that more storms are forecast in the coming days.

"The rainstorms triggered flash floods and mud-rock flows, swollen rivers, burst dikes, threatened reservoirs, and damaged highways, bridges and power and telecommunication facilities," it said.

It said the death toll rose to 70 after five people listed as missing in the eastern province of Jiangxi were found dead on Sunday.

As of Friday, the storms had affected up to 2.55 million residents and 100,000 hectares of arable land, and toppled 9,900 houses, the Office of State Flood Control and Drought Relief Headquarters said in a statement.