Emergency crews were desperately searching the wreckage of Plaza Towers Elementary School that took a direct hit from the tornado on Monday afternoon, Oklahoma Lieutenant Governor Todd Lamb told CNN.
There was an outpouring of grief on the school`s Facebook page, with messages from around the country including one pleading simply: "Please find those little children."
Another elementary school, homes and a hospital were among the buildings leveled, leaving residents of the town of about 50,000 people stunned at the devastation and loss of life.
The Oklahoma medical examiner said 20 of the 91 expected to have been killed were children. The office had already confirmed 51 dead and had been told by emergency services to expect 40 more bodies found in the debris, but had not yet received them.
At least 60 of the 240 people injured were children, area hospitals said.
"We thought we died because we were inside the cellar door ... It ripped open the door and just glass and debris started slamming on us and we thought we were dead to be honest," Ricky Stover said while surveying the devastated remains of his home.
Moore was devastated with debris everywhere, street signs gone, lights out, houses destroyed and vehicles tossed about as if they were toys.
Rescuers were searching for survivors throughout the swath of devastation into the early hours of Tuesday, while the dangerous storm system threatened several southern Plains states with more twisters. Severe weather was expected through the night from the Great Lakes south to Texas.
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