TUSCALOOSA, Ala. — A wave of tornado-spawning storms strafed the South on Wednesday night, splintering buildings across hard-hit Alabama and killing more than 250 people across the region.

In Tuscaloosa, a massive tornado barreled through the area. Sections of the city that’s home to the University of Alabama have been destroyed, the mayor said, and the city’s infrastructure was devastated.

Farther north, a nuclear power plant west of Huntsville lost power and was operating on diesel generators.

In Tuscaloosa, news footage showed paramedics lifting a child out of a flattened home, with many neighboring buildings in the city of more than 83,000 also reduced to rubble. A hospital there said its emergency room had admitted about 100 people, but had treated some 400. Charts weren’t even started for many patients because so many people were coming in at once. By midnight, only staff and patients were allowed inside.

“What we faced today was massive damage on a scale we have not seen in Tuscaloosa in quite some time,” Mayor Walter Maddox told reporters, adding that he expected his city’s death toll to rise.

President Barack Obama said he had spoken with Alabama Gov. Robert Bentley and approved his request for emergency federal assistance, including search and rescue assets.

“Our hearts go out to all those who have been affected by this devastation, and we commend the heroic efforts of those who have been working tirelessly to respond to this disaster,” Obama said in a statement.

Around Tuscaloosa, traffic was snarled Wednesday night by downed trees and power lines, and some drivers abandoned their cars in medians. University of Alabama officials said there didn’t appear to be significant damage on campus, and dozens of students and locals were staying at a 125-bed shelter in the campus recreation center.

Volunteers and staff were providing food and water to people like 29-year-old civil engineering graduate student Kenyona Pierce.

“I really don’t know if I have a home to go to,” she said.

Maddox said authorities were having trouble communicating, and 1,400 National Guard soldiers were being deployed around the state. The flashing lights of emergency vehicles could be seen on darkened streets all over town, and some were using winches to remove flipped vehicles from the roadside.

In a commercial district near the university, students with flashlights checked out the damage. Signs were blown down in front of restaurants, businesses were unrecognizable and sirens whaled off and on throughout the night.