LIMA (Reuters) - The body of one of seven miners trapped under a landslide for four days in southern Peru was pulled from a 200-meter (660 feet) deep tunnel on Friday, but hopes of finding the others alive dimmed, authorities said.

The miners had been working in an underground copper mine owned by Chinchilico Minero SAC in the region of Arequipa when more than 50 meters of mud and rock piled on top of the entrance during a downpour on Monday.

One miner managed to escape on Tuesday and reported that three of his seven colleagues inside had been alive when he left. But no sign of life has been heard since Wednesday, said Jorge Martinez, a chief of Peru’s all-volunteer firefighting force in Arequipa.

“We shouldn’t be pessimistic, we have to keep working until the end,” policeman Helbert Espinoza said on TV station Canal N.

The rescue effort stalled on Thursday after an electrical generator needed to power equipment broke down and the arrival of brigadiers was delayed by poor weather.

The government said it provided a pump and additional pumps and generators were on the way.

Chinchilico said it could not immediately provide comment.

The mine is one of tens of thousands of “informal” mines registered in a government program that aims to ensure that tax, labor and environment laws are enforced in Peru’s vast wildcat mining industry, the energy and mines minister said.