Mexican rescuers dug for a fourth day on Wednesday to reach 65 miners trapped in deep, unstable coal shafts and asked victims' families not to lose hope, despite making little progress.
About 60 rescue workers, mainly local miners, dug through the night with picks and shovels at the Pasta de Conchos mine in the northern state of Coahuila to reach the men.
"Don't lose hope. The work we're doing is to get out survivors, not bodies," head rescuer Josua David Beltran told a crowd of hundreds gathered at the mine late on Tuesday.
The gas that rescuers have found so far in the mine has not been at poisonous levels, he said. That raised hopes there could still be survivors, even though there has been no contact with any of the missing men since a gas explosion collapsed hundreds of yards of tunnels early on Sunday.
The missing men were carrying oxygen tanks with six hours of air in them, so their chances for survival depend on air pockets inside the tunnels or on the mine's ventilators.
The rescuers used hand tools to avoid sparking a new blast in the mine, near the town of San Juan de Sabinas.
Hundreds of friends and relatives camped outside of the mine on Tuesday night, lighting bonfires to keep warm.
Yadira Gallegos, whose brother-in-law is among the trapped miners, sat in a plastic chair with a blanket over her legs.
"The rescuers are doing everything humanly possible, but the government and the company didn't do what they should have," said Gallegos, 28. "They didn't give (the workers) the safety they deserve."
Rescuers remained within 55 yards (50 metres) of where two of the men were thought to have been working on a conveyor belt at the time of the blast. Additional collapses in the tunnels have hampered their progress, reports Reuters.
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