Rescuers were tearing through rubble at both the Plaza Towers Elementary School and the Briarwood Elementary School in nearby Moore, said Lt. Kevin Parton, public information officer for the police department in Oklahoma City.
Television news accounts and the Associated Press reported several children had been pulled alive from the rubble of the Plaza Towers school.
"Our hearts are just broken for the parents" trying to find out the fate of their children who were at one of the two schools, Oklahoma Gov. Mary Fallin said during a news conference Monday night.
Students and faculty took shelter inside both school buildings when the tornado hit, and Parton said he'd been told that teachers shielded children with their bodies in both school buildings when the strong winds ripped the roofs away.