People watch the search fo survivors at a collapsed illegal gold mine in Santander de Quilichao, southern Colombia. (AP Photo/Oswaldo Paez, El Pais)

Bogota - The death toll from a landslide at an illegal gold mine in western Colombia has risen to 12, authorities said Monday, as rescuers searched for four more missing victims.

The open pit mine was being worked by miners with hand tools when it was hit last Wednesday by an avalanche of mud, rock and earth.

“On Sunday we discovered an additional person, a woman. In total, nine victims have been recovered, plus the three found dead the day of the collapse,” said Lieutenant Colonel Mauricio Cardenas, director of operations in western Cauca state where the incident took place.

Rescuers aided by police dogs were carefully searching the unstable terrain by hand to avoid damaging the remaining bodies.

Several bodies have already been identified and returned to their families, Cardenas said, adding that search operations will continue “until we find the last one.”

The unlicensed mine, located in the rural community of Santander de Quilichao, will be closed once the search operation is finished, officials said.

Since the beginning of the year, 25 mining accidents have occurred in Colombia, half of them involving unlicensed gold mining operations, according to the National Mining Agency.

Colombia has upwards of 14 000 mines, more than half of which operate without proper permits, officials say.