TUSCALOOSA, Ala. - (AP) - Southerners found their emergency safetynet shredded Friday as they tried to emerge from the nation'sdeadliest tornado disaster since the Great Depression. Emergency buildings are wiped out. Bodies are stored inrefrigerated trucks. Authorities are begging for such basics asflashlights. In one neighborhood, the storms even left firefightersto work without a truck. The death toll from Wednesday's storms reached at least 340 across sevenstates, including 238 in Alabama, making it the deadliest U.S.tornado outbreak since March 1932, when another Alabama stormkilled 332 people. Tornadoes that swept across the South andMidwest in April 1974 left 315 people dead. Hundreds if not thousands of people were injured Wednesday - 990in Tuscaloosa alone - and as many as 1 million Alabama homes andbusinesses remained without power. The scale of the disaster astonished President Barack Obama whenhe arrived in the state Friday. "I've never seen devastation like this," he said, standing inbright sunshine amid the wreckage in Tuscaloosa, where at least 45people were killed and entire neighborhoods were flattened. Mayor Walt Maddox called it "a humanitarian crisis" for hiscity of more than 83,000. Maddox said up to 446 people were unaccounted for in the city,though he added that many of those reports probably were frompeople who have since found their loved ones but have not notifiedauthorities. Cadaver-detecting dogs were deployed in the cityFriday but they had not found any remains, Maddox said. During the mayor's news conference, a man asked him for helpgetting into his home, and broke down as he told his story. "You have the right to cry," Maddox told him. "And I can tellyou the people of Tuscaloosa are crying with you."