Mississippi Emergency Management Agency spokesman Greg Flynn said five people were killed in Choctaw County, 3 in Yazoo County and 1 in Holmes County. No names have been released and details are not available.
Two of those dead in Choctaw county are children.
Gov. Haley Barbour told The Associated Press there was "utter obliteration" in parts of Yazoo County, an area where he is from. More than 15 other counties were also damaged.
The swath of debris forced rescuers to pick up some of the injured on all-terrain vehicles.