Rescuers have found a body of one of 13 miners trapped more than 200ft (61m) below ground in a coal mine in the US state of West Virginia.
Friends and relatives have been waiting more than 35 hours for news
Rescue teams have not been able to determine the location of the remaining men, despite digging more than two miles into the Sago mine.
There has been no communication with the miners since they were trapped by an explosion on Monday morning.
Officials say carbon monoxide levels underground are dangerously high.
The miners had with them a day's worth of food and water supplies, and are equipped with individual air purifying systems that would give them up to seven hours of clean air, officials have said.
US President George Bush said the nation was praying for the men, and he offered federal help to bring them out alive.
The body was found in an area that appears to have taken the force of the explosion, and is being brought to the surface for identification. It appears the man was working separately from the other 12.
"Hopes certainly are stretched thin at this point," said Ben Hatfield, the head of the International Coal Group (ICG) mining company.
Friends and relatives gathered at a church near the mine were "passing out and crying and just really in a bad shape", Red Cross volunteer Tamila Swinger said.
However, Mr Hatfield said it was a "very good thing" that the small vehicle used to transport the 12 men as they travelled deep into the mine was found empty.
It suggests the miners may have survived the force of the blast and moved out of the vehicle to escape.
At an earlier press conference, Mr Hatfield said that there was a chance the miners had managed to take shelter from the toxic gas levels.
The explosion happened as miners resumed operations after the holidays, officials said.
A second six-member crew moving behind the group of 12 men - with an average of 23 years' experience in mining - heard the explosion but managed to escape unharmed.
ICG says it has no indication of what caused the blast.
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