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ATLANTA - Tornadoes across the southern United States killed at least 20 people as they tore up a hospital and high school where students huddled for shelter, authorities said today, a day after the rampage.
The toll from the severe weather could rise. The US Coast Guard said six people were missing Friday after their 23-foot (7-metre) vessel began taking on water in stormy seas off Myrtle Beach, South Carolina, on Thursday night.
The tornadoes killed nine people in Georgia, where a hospital was hit, and 10 people in two southern Alabama towns, officials said.
The powerful storms, which levelled scores of homes while flipping cars into the air and leaving thousands stranded without power, also killed a young girl in a mobile home in Missouri, the officials said.
In Georgia, two died in the town of Americus when the Sumter Regional Hospital was hit by a tornado, and six died, including two children, in hard-hit Baker County. The ninth fatality was in Taylor County, a north of Americus, said state emergency management official Michael Parker.
"I was shocked. It was worse than I had feared," Georgia Gov. Sonny Perdue told reporters in Americus after he had toured damage from the storms. "It's just a blessing that we didn't have more fatalities."
Tara Emnett, an official at the Enterprise mayor's office in Alabama, said all but one of the nine victims there were students at the high school, a shredded building left surrounded by broken trees and overturned cars.
Another fatality in Enterprise occurred in a residence, Emnett said. Emergency management officials confirmed at least one storm-related death elsewhere in Alabama, in Wilcox County.
Students in hallways
The high school's students had been assembled in hallways when the storm hit, in line with emergency procedures, said Coffee County Emergency Management director John Tallas, whose area of responsibility includes Enterprise.
"They were in the hallway of the school which typically is the most structurally sound part of the building," Tallas told CBS television's Early Show.
Students interviewed on the program said the hallway's roof caved in soon after they gathered there.
"I just sat down. The next thing I knew windows and stuff were busting everywhere," student Robert Humphrey said.
"When the tornado first hit it got real loud," Brent Smith, another student, told CNN. "When it quieted down you could hear people calling for help and all ... It was real chaotic."
Doctors at Medical Centre Enterprise treated more than 50 people for lacerations, broken bones and other injuries, hospital chief executive Jeff Brannon said. Most were hurt at the school.
Hospital workers had rushed to move patients away from the windows as sirens screamed out a warning moments before a dark funnel cloud roared past. Hospital windows burst and cars were pummelled in the hospital parking lot, Brannon said.
The same weather system that triggered the tornadoes hit the upper Midwest, causing blizzards. Storm-related traffic accidents were reported in Wisconsin and North Dakota and air travel disrupted across a wide area.
US President George W. Bush said he would visit devastated parts of both Alabama and Georgia on Saturday.
Thursday's storms came just a month after a tornado killed about 20 people in central Florida.
The height of the tornado season in the United States does not begin until May, but winter tornadoes are common in years which experience the El Nino phenomenon -- an unusual warming of Pacific waters that can bring torrential rain to some parts of the globe and extreme drought to others.
- REUTERS