Massive tornado hits Oklahoma

A woman carries her child through a field near the collapsed Plaza Towers Elementary School in Moore, Okla., May 20, 2013.

An American flag blows in the wind at sunrise atop the rubble of a destroyed home a day after a tornado moved through Moore, Okla., May 21, 2013.

Dana Ulepich searches inside a room left standing at the back of her house destroyed after a powerful tornado ripped through Moore, Okla., May 20, 2013.

A member of a security team helps guard an area of rubble from a destroyed residential neighborhood, one day after a tornado moved through Moore, Okla., May 21, 2013.

Teachers carry children away from Briarwood Elementary school after a tornado destroyed the school in south Oklahoma City, May 20, 2013.

A fire burns in the Tower Plaza Addition in Moore, Okla., following a tornado Monday, May 20, 2013. A tornado as much as a mile (1.6 kilometers) wide with winds up to 200 mph (320 kph) roared through the Oklahoma City suburbs Monday, flattening entire nei — AP Photo Sue Ogrocki

A fire burns in the Tower Plaza Addition in Moore, Okla., following a tornado Monday, May 20, 2013. A tornado as much as a mile wide with winds up to 200 mph roared through the Oklahoma City suburbs Monday, flattening entire neighborhoods, setting buildings on fire and landing a direct blow on an elementary school.

This aerial photo shows the remains of homes hit by a massive tornado in Moore, Okla., Monday May 20, 2013.

A boy is pulled from beneath a collapsed wall at the Plaza Towers Elementary School following a tornado in Moore, Okla., Monday, May 20, 2013.

A storm system that generated an EF4 tornado is captured at 19:40 UTC on May 20, 2013 over Moore, Okla.

Damaged vehicles are piled up in front of the Moore Warren Theater after a powerful tornado ripped through Moore, Okla., May 20, 2013.

A child is carried from the rubble of the Plaza Towers Elementary School following a tornado in Moore, Okla., Monday, May 20, 2013.

People react in front of the Plaza Towers Elementary school in Moore following a deadly tornado, May 20, 2013.

BKvsU1OCIAAa0FL.jpg_large.jpg — Oklahoma County Sheriff

Scared, but this little pup survived in Moore, Okla., Monday, May 20, 2013. A tornado as much as a mile wide with winds up to 200 mph roared through the Oklahoma City suburbs, flattening entire neighborhoods, setting buildings on fire and landing a direct blow on an elementary school.

Cars marked with an orange 'X', denoting they had been checked for occupants, are piled up in what was the front entrance to the damaged Moore Medical Center after a powerful tornado ripped through Moore, Okla., May 20, 2013.

Dana Ulepich looks at the debris from her house destroyed after a powerful tornado ripped through Moore, Okla., May 20, 2013.

This dramatic photo of a giant twister in the rear-view mirror was taken by a driver leaving Moore, Okla., as a series of tornadoes, up to a mile wide in total, caused devastation across Oklahoma City's suburbs on May 20, 2013.

This aerial photo shows the remains of homes hit by a massive tornado in Moore, Okla., May 20, 2013.

People walk through a damaged area near the Moore Warren Theater after a powerful tornado ripped through Moore, Okla., May 20, 2013.

A child is pulled from the rubble of the Plaza Towers Elementary School in Moore, Okla., and passed along to rescuers Monday, May 20, 2013. A tornado as much as a mile wide with winds up to 200 mph roared through the Oklahoma City suburbs, flattening entire neighborhoods, setting buildings on fire and landing a direct blow on an elementary school.

This aerial photo shows the remains of homes hit by a massive tornado in Moore, Okla., May 20, 2013.

Onlookers watch as children are pulled from the rubble of the Plaza Towers Elementary School following a tornado in Moore, Okla., May 20, 2013.

A woman carries her child through a field near the collapsed Plaza Towers Elementary School in Moore, Okla., Monday, May 20, 2013. — AP Photo Sue Ogrocki

A woman carries her child through a field near the collapsed Plaza Towers Elementary School in Moore, Okla., May 20, 2013.

A woman carries an injured child to a triage center near the Plaza Towers Elementary School in Moore, Okla., May 20, 2013.

A child calls to his father after being pulled from the rubble of the Tower Plaza Elementary School following a tornado in Moore, Okla., May 20, 2013.

Screen grab of damage in Moore, Oklahoma from massive tornado that swept through on Monday afternoon.

Scenes of devastation in Moore, Okla., after a massive series of tornadoes tore through the are on May 20, 2013.

A building flattened by Monday's massive tornado is seen in Moore, Okla.

A boy is pulled from beneath a collapsed wall at the Plaza Towers Elementary School following a tornado in Moore, Okla., May 20, 2013.

Moore police dig through the rubble of the Plaza Towers Elementary School following a tornado in Moore, Okla., May 20, 2013.

BKvrDLkCIAAhDCp.jpg_large.jpg — Oklahoma County Sheriff

A U.S. flag lays among debris in Moore, Okla., May 20, 2013 following a tornado up to a mile wide which swept through the Oklahoma City suburbs.

BKt-L3PCUAE1XF0.jpg_large.jpg — Oklahoma County Sheriff

Rescue personnel fold a U.S. flag in Moore, Okla., May 20, 2013 following a tornado up to a mile wide which swept through the Oklahoma City suburbs.

Screen grab of damage in Moore, Okla. from massive tornado that swept through on Monday afternoon.

Okla. governor on tornado's destruction — CBS News

A massive tornado ripped through the Oklahoma City suburb of Moore, May 20, 2013.

Screen grab of damage in Moore, Okla. from massive tornado that swept through on Monday afternoon.

A tornado rips through the Oklahoma City area Monday afternoon, May 20, 2013.

A tornado caused major devastation in Oklahoma City Monday afternoon. — KWTV

Screen grab of damage in Moore, Okla. from massive tornado that swept through on Monday afternoon.

Another very large tornado was seen touching down near Oklahoma City, Okla. on Monday afternoon, May 20, 2013.

Seven-year-old Katrina Ash watches with her mother, Amber Ash, as heavy equipment is brought into their tornado damaged neighborhood near Dale, Okla., May 19, 2013. Residents were not being allowed into the neighborhood as search and rescue operations continued.

Seven-year-old Katrina Ash holds a doll as she waits with her grandfather, Michael Bowen, after a tornado ripped through their neighborhood near Dale, Okla., May 19, 2013. Residents are not being allowed back into the neighborhood as search and rescue efforts take place.

Debris is kicked up by a twister, one of several tornadoes that struck parts of the nation's midsection, May 19, 2013.

Maeghan Hadley, of One Day Ranch pet rescue, checks a kitten pulled from the rubble of a mobile home destroyed by Sunday's tornado in the Steelman Estates Mobile Home Park, near Shawnee, Okla., May 20, 2013.

A resident searches through the rubble of his mobile home, in the Steelman Estates Mobile Home Park, destroyed by Sunday's tornado, near Shawnee, Okla., May 20, 2013. The tornado that slammed into Oklahoma on Sunday is now blamed for two deaths. Authorities say two men in their 70s have been found dead in or near a mobile home park outside of Shawnee.

Members of the Chickasaw Nation search and rescue group dig through debris, May 20, 2013, to locate a kitten buried in the rubble of a mobile home destroyed in Sunday's tornado, in the Steelman Estates Mobile Home Park, near Shawnee, Okla.

Residents of Edmond, Okla., survey storm damage from a tornado that hit their neighborhood Sunday, May 19, 2013.

People survey damage from a tornado that hit Edmond, Okla., May 19, 2013.

Volunteers help clean out Jean McAdams' mobile home near Shawnee, Okla., after it was overturned by a tornado May 20, 2013.

An electrical pole lies on a Pottawatomie County road near Shawnee, Okla., after a tornado touched down there, May 20, 2013.

One of several tornadoes which touched down in the U.S. Midwest, May 19, 2013, afflicting severe damage in central Oklahoma and Wichita, Kan. One person was killed near Shawnee, Okla., and 21 injuries were reported throughout the state.

Volunteers help with cleanup of Tom and Ronda Clark's property near Shawnee, Okla., after it was damaged by a tornado May 20, 2013.

A piece of corrugated tin is draped over a power line near Shawnee, Okla., after a tornado swept through the area on May 20, 2013.

Candice Lopez (L) and Stephanie Davis help clean debris from Thelma Cox's mobile home near Shawnee, Okla., after it was destroyed by a tornado May 20, 2013.

A twister approaches the home of Bryan Bedford in south Oklahoma City, May 20, 2013.