At least 25 people have been killed after several tornadoes touched down shortly before 1 a.m. Tuesday morning in Middle Tennessee, with one causing major damage in Nashville.

At least 18 people died in Putnam County alone, according to Tennessee Department of Health. The other fatalities were spread throughout Wilson, Davidson and Benton counties. According to Putnam County Mayor Randy Porter, several people remained unaccounted on Wednesday.

More than 140 buildings were destroyed in Middle Tennessee in the early hours of Tuesday. One of the hardest-hit areas was West Nashville, where there were reports of heavy damage to planes and hangars at the John C. Tune Airport, according to WKRN.com.

At one point more than 73,000 homes and businesses remained without power across four counties, according to the state emergency agency.

There were reports of seven tornadoes from late Monday into Tuesday morning in parts of Missouri, Kentucky and Tennessee. The exact number of tornadoes won't be known for several days, as the National Weather Service continues to conduct surveys and assign ratings.