MOORE, Okla. -- A monstrous tornado at least a half-mile wide roared through the Oklahoma City suburbs Monday, flattening entire neighborhoods and destroying an elementary school with a direct blow as children and teachers huddled against winds up to 200 mph.

At least 51 people, including at least 20 children, were killed, according to Amy Elliott, spokeswoman for the state medical examiner's office. Officials said the death toll was expected to rise.

The storm laid waste to scores of buildings in Moore, a community of 41,000 people south of the city. Block after block lay in ruins. Homes were crushed into piles of broken wood. Cars and trucks were left crumpled on the roadside.

Late Monday night, President Barack Obama declared the area a major disaster, making it eligible for federal aid.

"I'm sick to my stomach," said Jayme Shelton, a Moore city spokesman, reached by telephone. "Send your prayers this way."

Shelton said the city's roughly 160 police officers and firefighters were going door-to-door, checking for people who might be trapped in the rubble. Search-and-rescue teams poured in from every corner of the state.

"This is terrible. This is war-zone terrible," said a helicopter reporter for KFOR-TV Channel 4 in Oklahoma City. "This whole area is destroyed. The houses are destroyed, completely leveled."

The National Weather Service issued an initial classification of the tornado as an EF-4 on the enhanced Fujita scale, the second most-powerful type of twister.

More than 120 people were being treated at hospitals, including about 70 children.

Rescuers launched a frenzied effort at the Plaza Towers Elementary School, pulling children from heaps of debris and carrying them to a triage center.

Oklahoma Gov. Mary Fallin deployed 80 National Guard members to aid in search-and-rescue operations. She also activated extra highway patrol officers.

Many landlines to stricken areas were down and cellphone traffic was congested.

The storm was so massive that it will take time to establish communications between rescuers and state officials, the governor said.

In video of the storm, the dark funnel cloud could be seen marching slowly across the green landscape. As it churned through the community, the twister scattered shards of wood, pieces of insulation, awnings, shingles and glass all over the streets.

At Plaza Towers Elementary, the storm tore off the roof, knocked down walls and turned the playground into a mass of twisted plastic and metal.

Rescuers pulled several students alive from the rubble. Rescue workers passed the survivors down a human chain to the triage center in the parking lot.

James Rushing, who lives across the street from the school, heard reports of the approaching tornado and ran to the school, where his 5-year-old foster son, Aiden, attends classes. Rushing believed he would be safer there.

"About two minutes after I got there, the school started coming apart," he said.

Douglas Sherman drove two blocks from his home to do what he could to help rescue any survivors. "Just having those kids trapped in that school, that really turns the table on a lot of things," he said.

Tiffany Thronesberry said she got an alarming call from her mother, Barbara Jarrell, after the tornado.

"I got a phone call from her screaming, 'Help! Help! I can't breathe. My house is on top of me!' " Thronesberry said.

Thronesberry hurried to her mother's house, where first responders had already pulled her out. She was hospitalized for treatment of cuts and bruises.

At nearby Briarwood Elementary, teachers carried children away after tornado destroyed the school.

Search and rescue efforts were to continue throughout the night.

"It's as bad as it looks," Rep. James Lankford, R-Okla., whose district includes most of neighboring Oklahoma City, said Monday night as he left the House floor, checking his phone for updates.

Oklahoma City Police Capt. Dexter Nelson said downed power lines and open gas lines posed a risk in the aftermath of the system.

The weather service estimated that the storm that Monday's tornado was at least a half-mile wide.

A May 1999 storm with a similar path had winds clocked at 300 mph. That E5 twister killed 42 people in the area of Moore.

Kelsey Angle, a weather service meteorologist in Kansas City, Mo., said its unusual for two such powerful tornadoes to track roughly the same path.

It was the fourth tornado to hit Moore since 1998. A twister also struck in 2003. Monday's devastation in Oklahoma came almost exactly two years after an enormous twister ripped through the city of Joplin, Mo., killing 158 people and injuring hundreds more.

With The Washington Post

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