LIMA, Peru -- Peru's mining minister has appealed to mining companies for heavy equipment and experts to free nine miners trapped for four days in an informal copper mine.
Several dozen rescue workers have been using pickaxes and shovels to try to remove the 26 feet (eight meters) of collapsed earth and rock blocking the entrance of the mine, whose horizontal shaft is dug into a mountain.
TV images of the effort showed firefighters Sunday chopping wooden beams to support the effort.
Thursday's collapse occurred after a blast set by the miners themselves.
Rescuers have been able to communicate with the trapped miners and provide them with liquid sustenance through a tube.
Mining is the main engine of Peru's economy, accounting for more than 60 percent of its exports.
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