Rescuers combed through rubble on Saturday after a powerful storm tore across Mississippi late on Friday, killing at least 21 people, as it leveled hundreds of buildings and spawned at least one devastating tornado.

Rescue crews searched for victims Monday amid the splintered lumber and twisted metal where homes once stood, after the deadliest U.S. tornado in nearly six years ripped through a rural Alabama community. At least 23 people were killed, some of them children.