Rescuers are still looking for 22 unaccounted people after tornadoes wrecked havoc in Tennessee.

Tuesday was the deadliest tornado day for seven years with the storms destroying hundreds of buildings and claiming the lives of 24 people.

The number of people unaccounted for has shifted over the last couple of days, being as high as 80 at one point and down to 22 currently.

Meg Selby and Marc Warren, a couple in Tennessee spoke to CNN about what happened when the tornado hit.

"It went from being kind of a precautionary thing to living through something very catastrophic," said Ms Selby.

Mr Warren added: "It got quiet, and you could hear this sort of slow roar, and it just got gradually louder and louder."

Search and rescue teams are inspecting damaged homes in Putnam County. Mayor Randy Porter insists officials are doing all they can to make sure everyone is accounted for.

"We're hoping that most of those are people that are safe and just haven't let us know that they are," Mr. Porter said.

"The area is still very devastated."

The storm hit as hundreds of thousands of voters were going to the polls to choose a Democratic nominee as part of Super Tuesday.

This affected opening times for certain polling stations and a Democratic Party spokeswoman confirmed a judge ruled some of the polls had to extend their hours.