Kentucky's governor on Sunday asked the federal government to declare the aftermath of tornadoes that have devastated the state a major federal disaster, the head of U.S. disaster response agency said.

Federal Emergency Management Agency chief Deanne Criswell said at a press conference that the state's Governor Andy Beshear has formally made the request, which if granted would pave the way for additional federal resources to be provided.

Beshear said at least 80 people in the state were confirmed dead and the toll was eventually going to exceed 100, but he held out hope for "some miracles" even though it had been more than 24 hours since anyone was found alive in the rubble.

Eight people were confirmed dead and eight were still missing on Sunday at the Mayfield Consumer Products Candle Factory, where 110 employees were working when it was destroyed by tornadoes, a company spokesperson said on Sunday.

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.

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 warehouse in Illinois. A nursing home was struck in Arkansas, causing one of that state's two deaths. Four were reported dead in Tennessee and two in Missouri.