Search and rescue teams were also out in Rolling Fork, a town of 1,700 people that saw the brunt of the tornado, CNN reported.
"My city is gone, but we are resilient," Rolling Fork Mayor Eldridge Walker said on CNN.
According to Walker, 12 of the people who died were in Rolling Fork, adding several people were trapped in their homes.
Terrell compared the destruction to a tornado in Joplin, Missouri, that killed 161 people in 2011.
The reports stretched from the western edge of Mississippi north through the center of the state and into Alabama.