At least 23 people have been killed and several others injured after a tornado roared across south-east Alabama on Sunday.
Severe storms destroyed mobile homes, snapped trees and scattered destruction and weather warnings into Georgia, Florida and South Carolina.
Dozens of emergency responders rushed to join search and rescue efforts in Lee County, Alabama, after a large tornado touched down on Sunday afternoon, springing out of a powerful storm system.
“Unfortunately our toll, as far as fatalities, does stand at 23 at the current time,” Lee County Sheriff Jay Jones said of the death toll.
Drones flying overhead equipped with heat-seeking devices had scanned the area for survivors but the dangerous conditions halted the search late on Sunday, Mr Jones said.
An intense ground search would resume Monday morning.
Mr Jones said said the twister travelled straight down a key local artery in Beauregard and that the path of damage and destruction appeared at least half a mile wide.
Several people in Lee County were taken to hospitals, “some of them with very serious injuries”, he added.
The National Weather Service confirmed late on Sunday that a tornado with at least an F3 rating caused the deadly destruction in Alabama.
Radar and video evidence showed what looked like a large tornado crossing the area near Beauregard shortly after 2pm, said meteorologist Meredith Wyatt with the Birmingham, Alabama, office of the National Weather Service.
After nightfall on Sunday, the rain had stopped and pieces of metal debris and tree branches littered roadways.
President Donald Trump tweeted: “To the great people of Alabama and surrounding areas: Please be careful and safe. … To the families and friends of the victims, and to the injured, God bless you all!”
Rita Smith, spokeswoman for the Lee County Emergency Management Agency, said about 150 first responders had helped efforts to search the debris after the powerful storm hit.
No deaths had been reported on Sunday evening from storm-damaged Alabama counties outside Lee County, said Gregory Robinson, spokesman for the Alabama Emergency Management Agency.
But he said crews were still surveying damage in several counties in the south-western part of the state.
Numerous tornado warnings were posted across parts of Alabama, Georgia, Florida and South Carolina on Sunday afternoon as the powerful storm system raced across the region.
Weather officials said they confirmed other tornadoes around the region by radar alone and would send teams out early on Monday to assess the situation involving those and others.
The threat of severe weather continued into the late-night hours.
A tornado watch was in place for much of eastern Georgia, including Athens, Augusta and Savannah. The tornado watch also covered a large area of South Carolina, including the cities of Charleston and Columbia.