Aerial pictures have revealed the extent of the damage caused by the tornadoes that hit 11 US states last Friday.
At least 32 were killed when fierce storms spawned possibly dozens of tornadoes from the South and the Midwest into the Northeast.
Delaware, Arkansas and Illinois were among the worst-hit states.
Residents of Wynne, Arkansas, a community of about 8,000 people 80 kilometres west of Memphis, Tennessee, woke Saturday to find the high school's roof shredded and its windows blown out. At least four people died.