Cold, hungry and surviving on milk, 69 Chinese miners began a third night trapped underground after a rain-swollen river flooded much of the pit and blocked their exit.

Rescuers poured almost 400 litres (90 gallons) of milk down the ventilation pipes in the Zhijian mine in the central Henan province, hoping to keep the miners alive long enough for water to be pumped out of the shafts and silt to be cleared away.

The milk was sent down 800m-long ventilation pipes along with salty water and mineral water. The sustenance was delivered through a smaller tube installed inside a ventilation pipe extending to the area of the mine where the men have been trapped since early on Sunday.

A local reporter said: “We daren’t provide them with solid food in case this blocks the pipe.” None of the men was injured but they were cold and hungry. Experts from the State Safety Production Supervision Administration were able to maintain contact with them via a telephone line inside the mine even though the line had been soaked in the flood. The reporter said: “After drinking the milk the men felt more optimistic.”

The miners were dry and had electricity although ventilation was poor. Oxygen was also being piped into the pit. However, the rescue process was complicated and hundreds of rescuers were struggling to prevent more water from a flooded river from entering the mine after a deluge of more than 4,000cu m (141,000cu ft) poured through a disused shaft and flooded the mine.

The reporter said from the scene: “It’s hard to say when they can be rescued because there is water, mud and sand now in the mine. The rescue plan is having to be adjusted all the time in line with any progress.” By yesterday morning the water level in the mine had been reduced by 70cm (2ft 4in).

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