An F-4 tornado that was nearly a mile wide touched down in Moore, Okla., causing devastating damage, several injuries and at least 51 deaths.

The tornado touched down at about 2:53 p.m. CDT Monday in Moore, between Norman and Oklahoma City. Entire neighborhoods were leveled, according to local police.

Power lines were reported down on Santa Fe Road near the Briarwood Elementary School in Oklahoma City, Okla. It was reported that the elementary school had a large gas leak. Emergency crews experienced difficulty reaching the school due to large amounts of debris in the road.

Police reported that children were trapped under debris at the school. Later, police requested all available personnel report to help rescue the children from the debris. Children were reported to be lost and wandering in groups as parents searched the area.

Children at the Wellston Elementary School in Wellston, Okla., and Plaza Towers Elementary School in Moore, Okla., were also reported to be trapped under debris.

Injured people in Moore were being transported by police to the nearest roads clear of debris so they could be transported to medical facilities set up nearby.

Preliminary reports of at least 51 people killed and as many as 30 elementary students unaccounted for. At least 120 people are being treated for injuries.

Moore, Okla., was hit by an F-5 tornado on May 3, 1999. That tornado killed 44 people.