Cracks as deep as 10 meters have continued opening up in the middle of alfalfa fields in Chifeng City, north China's Inner Mongolia Autonomous Region, since July, as farmers delay harvesting for fear of injury.

Land resources and hydrological experts are researching the cause, but have not announced their findings yet.

"I had not seen anything like them in my whole life," said a 78-year-old local man surnamed Hou of Guangdegong Town.

The cracks appear in three patches and run east-to-west, with the longest ones stretching over 100 meters.

Hou said the farmland was very fertile and farmers previously used heavy machines for harvesting.

The area around the cracks is sinking and locals suspect that underground water overuse is the cause.

A 10-year drought has strickened Chifeng City. The cracks appeared after a brief but severe storm which brought rain and hail to the region in July, recalled local farmers.

According to the city's hydrological bureau, the city is facing a serious water shortage, with 62 percent of the city's 51 reservoirs dry. A total of 254,400 people are suffering drinking water shortages.

The bureau officials have admitted the city must dig more wells to alleviate the drinking water problem.