Rescuers have poured hundreds of liters of milk into a ventilation pipe to feed 69 miners who have been trapped in a flooded central China coal pit for three days.

The miners used their helmets to catch the milk, their only food since they were trapped in the flooded shaft at Zhijian colliery, in Shanxian county, Henan Province, early on Sunday.

"They told me that they felt much better after drinking the milk," said Shi Jichun, vice governor of Henan, after talking by phone with the miners.

Rescuers poured 382 liters of milk through the 800-meter ventilation pipe at around 9:00 p.m. on Monday, followed by another 167 liters on Tuesday morning.

They ruled out solid food for fear of blocking the pipe.

"The milk will help the miners keep their strength up, which is comforting," Shi said.

Rescuers have pumped about 2,000 cubic meters of water out of the mine and cleared about 100 cubic meters of mud in the shaft.

"The rescue operation is currently going on smoothly," said Shi. But he also said "the underground condition is complicated and the headquarters has worked out emergency plans for any new possible situation."

A caving-in which occurred around 3 p.m. Tuesday under the mine cut the telephone contact between the ground and the trapped miners. Communications workers managed to enter the shaft and managed to repair the telephone line and resume the contact two hours later.

"We are clearing mud and pumping water as quickly and effectively as possible," Henan Governor Li Chengyu told the miners by phone on Tuesday.

An estimated 4,000 cubic meters of water poured into the shaft when flood triggered by rainstorms swamped the mine at 8:40 a.m. on Sunday.

The rescue headquarters has arranged for six more pumps to ensure the pumping speed.

Altogether 102 miners were working in the pit when the flood occurred. Only 33 managed to escape.

Hundreds of rescuers, including armed police, are struggling to prevent more water from entering the shaft, clearing away the silt, and providing ventilation and oxygen to the trapped miners.

Li Yizhong, head of the State Administration of Work Safety, and Zhao Tiechui, head of the State Administration of Coal Mine Safety, are also at the coal mine overseeing the rescue efforts.

Li asked the local public security department to cooperate with the mine managers to clear the explosives underground to prevent new accidents.

The state-owned mine was established in 1958. It was designed to produce 210,000 tons a year, but its actual annual output is 300,000 tons.