

State Police in Montcoal, W.Va., monitor the entrance to the Massey Energy's Upper Big Branch mine where rescue and recovery efforts have been delayed again on April 9. Twenty-five miners are known to be dead and four remain missing from the explosion at the mine on Monday. Bob Bird/AP
Mourners gather during a candlelight vigil for the two coal miners who were killed and those still missing in Whitesville, W.Va. Chris Keane/Reuters
Miners sit together in front of Marsh Fork Elementary School on April 8. Rescuers waited Thursday for a massive drill to vent noxious gases in the mines so they could safely resume the underground search for four coal miners still missing after Monday's explosion. Rick Barbero/The Register-Herald/AP
Miner Brian Lemon waits near the Upper Big Branch mine in Montcoal, W.Va., on April 8. A small crowd of miners showed up to show their support for fellow miners on Thursday. Mike Munden/Reuters
Law officers move the media away from the Performance Coal Company mine entrance on April 8. Rick Barbero/The Register-Herald/AP
Howard Mitchell looks at a window display made up of miners' equipment and candles in Whitesville, W.Va., on April 8. The tribute includes a lit candle for each of the 25 miners known to be dead in Monday's explosion. Mark Humphrey/AP
A sign outside The Jesus Church along Coal River Road in Rock Creek, W.Va., calls for prayers for miners on April 8. Jeff Gentner/AP
A crowd gathers for a candlelight vigil in Oak Hill, W.Va., on April 7, held for William Roosevelt Lynch, a miner who was killed in Monday's explosion at Massey Energy's Upper Big Branch coal mine in Montcoal, W.Va. Jon C. Hancock/AP
People take part in a candlelight vigil walk through town on April 7 in Whitesville, W.Va., for miners in the explosion at the Upper Big Branch mine. Mark Humphrey/AP
A coal miner's wife attends a vigil in Oak Hill, W.Va., on April 7. Jon C. Hancock/AP
West Virginia Gov. Joe Manchin briefs reporters on the latest mine rescue operations on April 7 in Montcoal, W.Va. Haraz N. Ghanbari/AP
At St. Joseph's Catholic Church in Whitesville, W.Va., parishioners pray during a mass for coal miners killed in Monday's explosion on April 6. Rescue crews moved giant drills to the coal mine on Tuesday in hopes of boring deep inside to find four miners still missing. Chris Keane/Reuters
Massey Energy workers take a break from drilling efforts on April 7 in Montcoal, W.Va. Jeff Gentner/Reuters
A coal miner speaks about the miners who died on Monday in an explosion at Upper Big Branch mine. Bob Bird/AP
A large drill and fan (l.) work above Massey Energy's Upper Big Branch coal mine on April 7. The 560-foot rotary drill is the second hole drilled in an effort to release gas from the area where the miners are believe to be trapped. Jeff Gentner/AP
In an aerial photo, Massey Energy Complex in Montcoal, W.Va., is seen on April 6. Craig Cunningham/Charleston Daily Mail/AP
West Virginia State Police officers direct traffic in front of an entrance to Massey Energy's Upper Big Branch coal mine early April 6 after an explosion in the mine Monday. Micahel Henninger/Post-Gazette/AP
Specialist Evan Solomon (l.) directs trading in shares of Massey Energy Co. on the floor of the New York Stock Exchange on April 6. Though the cause of the blast that killed 25 West Virginia coal miners was not known, the operation run by Massey subsidiary Performance Coal Co. has a history of violations for not properly ventilating highly combustible methane gas, safety officials said. Richard Drew/AP
An entrance to Massey's Performance Coal is seen on April 6 after an explosion ripped through the coal mine on Monday in the deadliest US mining disaster since 1984. Chris Keane/Reuters
Ambulances wait at the scene of a mining accident in Montcoal, W.Va., in this image taken from video on April 5. After an explosion at Massey Energy's Upper Big Branch coal mine, rescuers searched for missing coal miners. WVVA-TV/Reuters
After an explosion at a coal mine in Montcoal, W.Va., State Police direct traffic near the entrance to Massey Energy's Upper Big Branch coal mine on Monday, April 5. Jeff Gentner/AP