Rescue workers in Kentucky on Sunday scoured debris for survivors as many residents without power, water or even a roof over their heads salvaged what they could after a string of powerful tornadoes that officials fear killed more than 100 people and obliterated homes and businesses.

Authorities said they had little hope of finding survivors after the tornadoes tore through the U.S. Midwest and South on Friday night, killing people in at least five states.

Six workers were killed at an Amazon.com Inc warehouse in Illinois after the plant buckled under the force of the tornado, including one cargo driver who died in the bathroom, where many workers said they had been directed to shelter.