Earthquake survivors rest on Tuesday after hunting for their belongings in the rubble in the town of Hanwang, in China's Sichuan province. (Eugene Hoshiko/Associated Press)

An estimated 80,000 people were forced to abandon their homes in China's earthquake-ravaged Sichuan province on Tuesday, amid fears that a massive lake is on the verge of flooding.

Emergency workers aimed to have all residents who live downstream from the Tangijashan lake in northern Beichuan county leave, state news agency Xinhua reported.

The lake formed when landslides triggered by the May 12 earthquake sent piles of debris into the Jianhe River, causing a lake to form that is believed to contain 128 million cubic metres of water.

More than 1,800 police and soldiers arrived at the site Monday and have been working ever since to pull the debris from the lake, which is on the brink of overflowing.

Meanwhile, the Chinese government announced Tuesday that the death toll in the quake has risen to 67,183, up by about 2,100 from the day before. Another 20,790 people are still reported missing.

Premier Wen Jiabao has suggested the death toll will eventually surpass 80,000.

The millions who survived are now struggling to find shelter, food and clean drinking water. Others are coping with the threat of landslides, with 1,300 forced to flee their homes in Quingchuan county due to landslide fears. Quingchuan official Li Guoping said 23,000 people in total may have to leave the area.

Adding to the threat Tuesday, thunderstorms were forecast for parts of Sichuan this week — a taste of the coming summer rainy season. At the same time, an earthquake expert said Tuesday that aftershocks, like the one that killed eight people on Sunday, could continue for months.

"Judging from previous earthquakes of a similar magnitude, this time the aftershocks may last for two or three months," He Yongnian, a former deputy director of China Seismological Bureau, told Xinhua.

With files from the Associated Press