Rescuers on Thursday declared the 29 miners trapped in a flooded iron ore mine in north China to be dead.

The rescue operation was reported to have ended on Tuesday after the underground water levels and air pressure rose to the point where survival became impossible.

Officials have begun discussing compensation with the victims' families, said a rescue official.

Thirty five miners were trapped when the mine, in Inner Mongolia Autonomous Region, was flooded on Jan. 17.  Six miners who were rescued the next day have received compensation of 5,000 yuan (641 U.S. dollars) each, plus some medical expenses, accommodation and travel fees from the mine company, said the official.

The tragedy occurred at the Haolaigou Iron Ore Mine in Donghe District of Baotou, when 46 miners were changing shifts. Only 11 miners escaped.

Problems appeared on the sixth day of the operation as the underground water level had risen 10 meters since Jan. 20 due to a slurry flow and subsidence.
 
As the hydraulic pressure rose, large amounts of slurry and water could flood the tunnels, threatening the lives of rescuers, said experts in the rescue team.

Rescuers tried to drill a hole with a diameter of 30 cm to the No. 3 shaft, through which they hoped to deliver oxygen and food to the trapped miners, who were believed to still have a chance of survival.

The operation has become extremely delicate on Jan. 22 as they tried to avoid more slurry flows or sudden rises in the water level.

After the accident, all mines in Baotou were ordered to suspend operations until they were proved legal and safe after a thorough examination.

Police are keeping Cao Shihu, legal representative of Chaoyue Mining Co. Ltd of Baotou City, which owns Haolaigou Iron Ore Mine, under surveillance.

With more than 100 employees, Chaoyue Mining is a private company set up in 2001. Its mines have a production capacity of 100,000 tons of iron ore concentrate a year.

The cause of the flooding remains unclear.

Inner Mongolia reported more than 84 mine accidents last year, including 23 coal mine accidents, and 124 deaths of miners, according to the regional work safety administration.

Zhao Shuanglian, vice chairman of the region, said the local government would step up efforts to improve qualifications of miners, eliminate outdated mining facilities and close unsafe mines.