Crews searched for more victims of deadly tornadoes that killed at least 55 people and injured hundreds more as they tore across five US states, ripping off a shopping mall roof, demolishing mobile homes and blowing apart warehouses. It was the country's deadliest barrage of twisters in almost 23 years. Dozens of tornadoes plowed across Mississippi, Arkansas, Tennessee, Kentucky and Alabama. The storms flattened entire streets, smashed warehouses and sent tractor-trailers flying. Houses were reduced to splintered piles of lumber. Some looked like life-size dollhouses, their walls sheared away. Crews going door to door to search for bodies had to contend with downed power lines, snapped trees and flipped-over cars. "We had a beautiful neighborhood. Now it's hell," said Bonnie Brawner, 80, who lives in Hartsville, Tennessee, a community about an hour from Nashville where a natural gas plant that was struck by a twister erupted in spectacular flames up to 400 feet (120 meters) high. "It looks like the Lord took a Brillo (scouring) pad and scrubbed the ground," said Tennessee Gov. Phil Bredesen, who surveyed the damage from a helicopter. Hundreds of houses were damaged or destroyed. Authorities had no immediate cost estimate of the damage. President George W. Bush gave assurances his administration stood ready to help. Teams from the Federal Emergency Management Agency were sent to the region and activated an emergency center in Georgia. "Loss of life, loss of property - prayers can help and so can the government," Bush said. "I do want the people in those states to know the American people are standing with them." Thirty-one people were killed in Tennessee, 13 in Arkansas, seven in Kentucky and four in Alabama, emergency officials said. It was one of the 15 worst tornado death tolls since 1950, and the nation's deadliest barrage of tornadoes since 76 people were killed in Pennsylvania and Ohio on May 31, 1985. Students took cover in dormitory bathrooms as the storms closed in on Union University in Jackson, Tennessee. More than 20 students at the Southern Baptist school were trapped behind wreckage and jammed doors after the dormitories came down around them. Danny Song was pinned for an hour and a half until rescuers dug him from the rubble. "We looked up and saw the funnel coming in. We started running and then glass just exploded," he said. "I hit the floor and a couch was shoved up against me, which may have saved my life because the roof fell on top of it." Most communities had ample warning that the storms were coming. Forecasters had warned for days severe weather was possible. The National Weather Service issued more than 1,000 tornado warnings from 3 p.m. Tuesday to 6 a.m. Wednesday in the 11-state area where the weather was heading. The conditions for bad weather had lined up so perfectly that the Storm Prediction Center in Norman, Oklahoma, put out an alert six days in advance. "All the clues were there. It was just unfortunate that it came out the way it did," prediction center director Joseph Schaefer said. While the weather was unusually severe, winter tornadoes are not uncommon. The peak tornado season is late winter through midsummer, but the storms can happen at any time of the year with the right conditions. The tornadoes could be due to La Nina, a cooling of the tropical Pacific Ocean that can cause changes in weather patterns around the world. Recent studies have found an increase in tornadoes in parts of the US South during the winter when La Nina occurs. There were 67 eyewitness accounts of tornadoes, but some of those were probably twisters that were counted more than once, said Greg Carbin, the warning coordination meteorologist at the Oklahoma center. The actual number is probably more like 30 or 40, he said. Some residents found reason to be thankful. In Castalian Springs, Tennessee, a baby was discovered unscathed in a field across from a demolished post office. A bystander swaddled the crying child in his shirt. There was no word on the fate of the child's parents. "He had debris all over him, but there were no obvious sings of trauma," said Ken Weidner, Sumner County emergency management director. Seavia Dixon, whose Atkins, Arkansas, home was shattered, stood in her yard, holding muddy baby pictures of her son, who is now a 20-year-old soldier in Iraq. Only a concrete slab was left from the home. The family's brand-new white pickup truck was upside-down, about 150 meters from where it was parked before the storm. Another pickup truck the family owned sat crumpled about 50 feet (15 meters) from the slab. "You know, it's just material things," Dixon said, her voice breaking. "We can replace them. We were just lucky to survive."