At least 15 mine workers were trapped in a gold mine in northwest Colombia Wednesday after it flooded and collapsed. Emergency rescue teams worked into the night attempting to free the workers trapped dozens of feet underground.

The workers are feared dead, given the difficulty of the rescue. The rescue operation is projected to take three days to be able to pump enough water to reach the miners, according to Colombia’s National Mining Agency.

Some of the those trapped were working at a depth of up to 55 feet at the time of the collapse, officials reported.

 Telesur