BEIJING - The death toll from nearly a week of heavy rain in southern China rose to 76 on Tuesday. 13 remains missing and tens of thousands were displaced.

A man inspects flood damage to his house in southeast China's Fujian province, 2006. [AFP]

More than 13.5 million people have been affected by the disaster, which has caused an estimated 4.73 billion yuan (606 million dollars) in economic losses, the civil affairs ministry reported on its website.

According to the ministry, 76 people have died and 13 are missing from torrential rains that have battered the region since June 6.

The death toll on Monday had stood at 66.

"At present the disaster situation is rather grave in some areas as there are a lot of people out there and the damage caused by water is serious," Li Ronggen, vice governor in charge of flooding in Guangdong province, said.

"On top of this the rain is continuing to fall, making the fight against flooding and other mitigating circumstances much more arduous," he said in a Tuesday statement posted on the website of the state flood headquarters.

Tens of thousands of people were safely evacuated from up to 24 villages that were submerged by floods in six provinces and regions in southern China, China Central Television said.

Guangdong province has been the worst hit and authorities there have deliberately diverted water to flood six villages so that more important towns and cities would not be inundated, Xinhua news agency reported.

The unavoidable flooding of villages occurred when authorities opened sluice gates at a dam on Guangdong's Hanjiang river because water there was building up to too high a level, it said.

"Landslides and collapses have been frequent along the river dam area," Guo Chunshan, the chief of Liuhuang town which encompasses the six villages, was quoted as saying.

"If we hadn't opened the discharge gate, the dam might have overflowed and the losses would have been much more serious," he added.

According to the ministry, 788,000 people have been evacuated from the six regions and provinces affected by the flooding -- Guangdong, Guangxi, Guizhou, Hunan, Fujian and Jiangxi.

More than 479,600 hectares (1.18 million acres) of farmland have been damaged by the disaster, with crops completely destroyed on nearly a third of the area, the ministry said.

More than 144,000 buildings and homes have been damaged by the floods and landslides, while 69,000 have been destroyed, it said.

The week of devastating rains has marked the start of the months-long storm season for southern and eastern China, although it began later than in 2006.

From April to August last year, natural disasters killed more than 2,200 people in China, with most deaths in the typhoon and flood-prone regions in the south and east, according to previously released government data.