BEIJING (AP) — China has evacuated at least 7,000 people after a dike broke over the weekend at Dongting Lake, the country's second-largest freshwater lake, in central Hunan province, state media reported on Monday.

According to the China Center for Resources Satellite Data and Applications (CRESDA), five satellites have been deployed to provide real-time monitoring of the affected areas.

The dam of Dongting Lake collapsed on Friday in Tuanzhou township of Hunan's Yueyang city, flooding the area. It forced the evacuation of at least 7,000 residents, Xinhua news agency reported.

Thousands of rescue workers, including firefighters, hydrologists, volunteers and police, are working to protect lives and properties.

Satellite images revealed widespread flooding in areas previously recognized as grassland or land.

Relief teams faced a new crisis on Monday as the embankment, seen as a second line of defence, was at risk after the embankment breached, state news agency Xinhua reported.

The local government said more than 300 police officers and firefighters were working to prevent the piping effect from destroying the embankment in Huarong County.

The 14.3-kilometre embankment is about two kilometers behind the embankment which breached after heavy rains.

The impact of the piping could hollow out the embankment and cause it to burst if not handled properly, Xinhua reports.

Thousands of rescue workers are working around the clock and closing the crack at a rate of 60 to 80 meters per day, reports said.

The 226 meter crack is expected to be sealed by Tuesday afternoon. So far, a 138.5 meter breach in the dam has been sealed.