As dawn broke over the ravaged Gulf of Mexico coast on Tuesday, rescuers in boats and helicopters furiously searched for survivors of Hurricane Katrina.
The governor said the death toll in one Mississippi county alone could be as high as 80.
Hurricane Katrina slams US Coast; kills 55
"The devastation down there is just enormous," Governor Haley Barbour said on a television show, the morning after Katrina howled ashore with winds of 233 kph.
Barbour said there were unconfirmed reports of up to 80 deaths in Harrison County, which includes Gulfport and Biloxi, and the number was likely to rise.
"We know that there is a lot of the coast that we have not been able to get to," the governor said.
"I hate to say it, but it looks like it is a very bad disaster in terms of human life."
Tree trunks, downed power lines and trees, and chunks of broken concrete in the streets hampered rescue efforts. Swirling water in many areas contained hidden dangers.
Hurricane Emily hits shore, weakens
Crews worked to clear the highways. Along one Mississippi highway, motorists themselves used chainsaws to remove trees blocking the road.
More than 1,600 Mississippi National Guardsmen were activated, and the Alabama Guard planned to send two battalions to Mississipi.
Late Monday night, Harrison County emergency operations center spokesman Jim Pollard said about 50 people had died in the county, with some 30 of the dead at a beach-side apartment complex in Biloxi.
Three other people were killed by falling trees in Mississipi while 2 died in a traffic accident in Alabama, authorities said.