More than one million people in China have been evacuated following downpours that have raised water levels in rivers to critical highs, and triggered floods and landslides, the government has said.

The summer rains have left at least 168 people dead or missing so far, and weather authorities warned Friday that flood-hit areas across the southern half of China would experience a fresh round of heavy rainfall.

"These areas must strengthen their prevention of geological disasters," the National Meteorological Centre said.

Authorities have evacuated more than one million people in eight provinces, regions and municipalities since June 9, the civil affairs ministry said late Thursday.

One waterway in the eastern province of Zhejiang has risen to its highest levels in 56 years, while other rivers across southern China have burst their banks, the nation's flood control headquarters added.

Some of the areas being pounded by rain -- such as Hubei and Hunan provinces -- were only recently in the thralls of a severe drought, which has in some cases made the situation worse.

A week ago, one landslide blasted through villages in Hunan before dawn, killing at least 19 people and leaving another eight missing. One village saw most of its houses buried by mud, state media reported.

Experts sent to investigate said the mudslide was triggered by the heaviest rain in the area in 300 years, adding the ground was drier than usual because of the drought, making it easier for downpours to sweep away sand and rocks.

China is hit by heavy summer rainfalls every year. In 2010, torrential downpours across large swathes of the country triggered the nation's worst floods in a decade, leaving more than 4,300 people dead or missing.

One devastating mudslide in the northwestern province of Gansu killed 1,500 people in August.