Four people were missing as search and rescue teams combed through the destruction looking for survivors after the storm struck Silver City in Western Mississippi, the Mississippi Emergency Management Agency said in a series of tweets on Saturday.
"Unfortunately, these numbers are expected to change," it said, referring to the death toll.
Search and rescue teams were also out in Rolling Fork, a town that faced the brunt of the tornado, CNN reported.
"I've never seen anything like this," Brandy Showah told CNN.Â
"This was a very great small town, and now it's gone."
At least 24 reports of tornadoes were issued to the National Weather Service overnight by storm chasers and observers.
Photographs of the destruction published by news networks showed entire buildings left in rubble and cars turned over on their sides as people climbed through the debris in darkness.
"Many in the MS Delta need your prayer and God's protection tonight," Governor Tate Reeve said in a tweet.
"We have activated medical support - surging more ambulances and other emergency assets for those affected. Search and rescue is active."
