West Virginia Medical Examiner's spokesman John Law says several bodies were received Saturday.
He did not know when the remaining victims will be transported from Massey Energy's Upper Big Branch mine to Charleston.
Twenty-nine miners were killed and two were injured last Monday the nation's worst coal mining disaster in 40 years. One miner remains hospitalized.
Families of four missing West Virginia miners got the news they had been dreading early Saturday morning, reports CBS News correspondent Terrell Brown, after rescue crews found the four miners still missing.
Initially, 25 men were known to have perished and two men survived. That left four unaccounted for, resulting in an agonizing week for relatives and authorities who hoped the miners had somehow managed to find refuge chambers stocked with food, water and oxygen. But none of the mine's refuge chambers had been deployed.
"We didn't receive the miracle we all prayed for," said Gov. Joe Manchin.
The conditions were so rough after the blast that rescuers only late Friday realized that they had walked past the bodies of the four missing miners on the first day without seeing, a federal mine safety official said.
"There was so much smoke and the conditions were so dire with dust in the air that they apparently bypassed the bodies that were on the ground," said Kevin Stricklin, coal administrator for the federal Mine Safety and Health Administration.
"The rescue workers told us they're sure no one suffered," Manchin said.
"They didn't know what hit them," said Patty Ann Manios, a city councilwoman from nearby Whitesville.
While watching the official announcement on TV, she took off her glasses and started to weep. "Oh God. Oh God."
The mission now is to recover all of the bodies still inside the Upper Big Branch mine.
Now a community in suspense for nearly a week will band together once again to bury their loved ones.
Federal Mine Safety and Health Administration spokeswoman Amy Louviere said the investigation into the cause of the blast started Saturday with the collection of material from the mine.
She says a team of investigators will arrive in West Virginia on Monday, and that the investigation is expected to take months to complete.
President Barack Obama said Saturday that there must be a thorough investigation and accountability in America's worst mining disaster in 40 years.
Mr. Obama made the statement after learning that four missing miners did not survive an explosion in the Upper Big Branch Mine in Montcoal, W.Va., operated by Massey Energy Co.
"All Americans deserve to work in a place that is safe, and we must take whatever steps are necessary to ensure that all our miners are as safe as possible so that a disaster like this doesn't happen again," Mr. Obama said.
Monday's blast was the worst U.S. coal mining disaster since a 1970 explosion killed 38 in Hyden, Ky.
More on the Upper Big Branch Mine Explosion:
4 Missing W.Va. Miners Found Dead
W.Va. Miners' Search Nears End, Officials Say
Funerals Begin for Miners
Funerals Begin for Miners Killed in W. Va. Explosion
Rescue Halted as Mine Air Turns "Explosive"
Mining Company was Cited on Day of Blast
Miners' Families Cling to "Sliver of Hope"
Mine Worker: "There are no Safe Mines"
W.Va. Coal Mine Blast: The Victims
Recent Fatal U.S. Mine Disasters
Mines not Paying Fines a Familiar Story
Gov.: "No Excuse" for Mine Safety Flaws
Eerie Statement from Miner Killed in Blast