Storms sweeping through southwest Georgia overnight left 11 people dead and 23 injured, the Georgia Emergency Management Agency told Reuters.
State officials did not immediately have details on the extent of the damage, noting that they were working with local authorities as the threat from severe weather continued.
In Mississippi, a predawn tornado on Saturday killed four people and caused widespread property damage.
The dangerous system prompted U.S. weather forecasters to issue a rare, “high risk” warning of severe storms threatening parts of southern Georgia, north Florida and Alabama on Sunday.
The last time the National Weather Service’s Storm Prediction Center in Norman, Oklahoma issued its highest risk warning for tornados was April 2014, lead forecaster Rich Thompson said in a telephone interview.
“These could be the kind of tornados you don’t want to mess with,” he said. “These could be fast-moving, kind of long-lived and could produce substantial damage if they encounter anything.”
He said 34 possible tornados had been reported in the past two days in a region stretching from the far eastern border of Texas, near the Louisiana state line, to Georgia.
Forecasters expected the hazards from the storm system would increase into the afternoon and continue through the evening.
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