A tornado at least a half mile-wide with 200mph winds churned through Oklahoma City's suburbs Monday afternoon, killing at least 37 and causing significant property damage for the second day in a row, forcing rescue crews to search for survivors in the debris of flattened homes, businesses and two schools.
Amy Elliott, a spokeswoman for the Oklahoma Medical Examiner's Office, said the death toll is expected to rise. Oklahoma City Police say seven of those deaths were children at Plaza Towers Elementary School, which was hit by the tornado, Fox 25 reports.
Oklahoma police told Fox News' Casey Stegall, on the ground in Moore, Okla., that at least four people were killed at a 7-11 convenience store. Integris Southwest Medical center in Oklahoma City said it received 19 patients, seven of which were in critical condition, Reuters reports.
The Oklahoma University Medical Center said it received 20 patients, including eight children, in trauma rooms at the University Medical Center and the nearby Children's Hospital at OU Medical Center.
Television footage on Monday afternoon showed homes and buildings that had been reduced to rubble in Moore, which is south of Oklahoma City. Footage also showed vehicles littering roadways south and southwest of Oklahoma City.
Search and rescue crews are now looking for anyone who may be trapped in the rubble, Fox 25 reports. Aerial flyovers showed crowds of residents picking through debris, while one resident told Fox News that children were trapped under cars at an elementary school.
Gary Knight with the Oklahoma City Police Department said the Briarwood Elementary School in Moore suffered "extensive damage."
At the Plaza Towers Elementary School, students were hugging and clinging to the walls of the school as the tornado passed over, KFOR reports.
An Associated Press photographer saw several children being pulled out of what was left of the school. The school's roof appeared mangled and the walls had fallen in or had collapsed.
Rescue workers lifted children from the rubble before they were passed down a human chain and taken to a triage center set up in the school's parking lot.
While the tornado was passing over the school, students were hugging and clinging to the walls, KFOR reports. There are 24 students believed to be in the rubble at the school, but the report could not be confirmed.
A Norman, Okla. regional health system spokesperson also told Fox News that Moore Medical Center, the only hospital in the city, also suffered "extensive structural damage," demolishing the second floor of the hospital and tearing off part of the roof.
The center evacuated 30 patients to two other hospitals in Norman, Okla.
The National Weather Service said the tornado was on the ground for nearly 40 minutes, with the first tornado warning coming 16 minutes before it touched down. The preliminary damage rating on the enhanced fujita scale was EF4 -- the second most-powerful type of twister -- and carved a 20-mile path through Newcastle, Moore and South Oklahoma City.
Oklahoma City Police Capt. Dexter Nelson said downed power lines and open gas lines now a risk for rescue teams in the aftermath of the system.
The Oklahoma Department of Transportation closed I-35 in both directions near Norman, Okla., to assist with cleaning up the debris.
"This is absolute devastation like nothing I've ever seen before," Betsy Randolph, with Oklahoma State Police, told Fox 25." This may be worse than the May 3rd, 1999 tornado."
The strongest winds on earth -- 302 mph -- were recorded near Moore that year.
On Monday night, President Barack Obama spoke with Oklahoma Gov. Mary Fallin to express his concern for those impacted by the storm. Obama said FEMA is ready to provide all available assistance as part of the recovery.
In advance of the storm, the Oklahoma House of Representatives stopped work so Capitol employees could take shelter in the basement. Television and radio broadcasters urged residents to take shelter because the storm's strength and size.
The Storm Prediction Center in Norman had predicted a major outbreak of severe weather Monday in Arkansas, Kansas, Missouri and Oklahoma. The National Weather Service has also issued tornado watches and warnings for counties in Missouri, Nebraska, Arkansas, Oklahoma and Texas.
On Sunday, at least two people were killed and 29 were injured in Oklahoma as a severe storm system generated several tornadoes in Kansas, Oklahoma and Iowa, leveling neighborhoods and sending frightened residents scurrying for shelter as extreme conditions are expected to linger across the Midwest.
The tornadoes, high winds and hail have been part of a massive, northeastward-moving storm system that has stretched from Texas to Minnesota.
At least four separate twisters touched down in central Oklahoma late Sunday afternoon, including one near the town of Shawnee, 35 miles southeast of Oklahoma City, that laid waste to much of a mobile home park.
Oklahoma state medical examiner's office spokeswoman Amy Elliott on Monday said the two people killed in the tornado were 79-year-old Glen Irish and 76-year-old Billy Hutchinson. Both men were from Shawnee.
Pottawatomie County Sheriff Mike Booth said one man, later identified as Irish, was found dead out in the open at Steelman Estates, but the sheriff didn't have details on where he had lived.
"You can see where there's absolutely nothing, then there are places where you have mobile home frames on top of each other, debris piled up," Booth said. "It looks like there's been heavy equipment in there on a demolition tour ... It's pretty bad. It's pretty much wiped out."
A storm spotter told the National Weather Service that the tornado "scoured" the landscape in the park and an area along Interstate 40. Officials said drivers should expect delays along the highway in Shawnee as crews continue to clean up storm debris. Westbound Interstate 40 was closed Sunday night at U.S. 177 after storms ripped through the area. U.S. 177 was also shut down because of vehicle accidents caused by the severe weather.
The Oklahoma Department of Transportation said northbound U.S. 177 at I-40 was reopened as of 7 a.m. Monday.
Gov. Mary Fallin declared an emergency for 16 Oklahoma counties because of the severe storms and flooding. The declaration lets local governments acquire goods quickly to respond to their residents' needs and puts the state in line for federal help if it becomes necessary.
Another tornado grazed the Oklahoma City suburb of Edmond Sunday afternoon, dropping hail as large as a grapefruit and damaging roofs and structures before heading east. Aerial flyovers in Wellston, northeast of Oklahoma City, showed significant property damage.
"I knew it was coming," said Edmond resident Randy Grau, who huddled with his wife and two young boys in their Edmond home's safe room when the tornado hit. He said he peered out his window as the weather worsened and believed he saw a flock of birds heading down the street.
"Then I realized it was swirling debris," Grau said. "That's when we shut the door of the safe room. I probably had them in there for 10 minutes."
Dozen of counties in Kansas, Nebraska, Iowa, Oklahoma, Minnesota, Wisconsin, Illinois and Missouri were placed under tornado watches and warnings that were in effect through late Sunday.
In Wichita, Kan., a tornado touched down near Mid-Content Airport on the city's southwest side shortly before 4 p.m., knocking out power to thousands of homes and businesses but bypassing the most populated areas of Kansas' biggest city. The Wichita tornado was an EF1 -- the strength of tornado on the enhanced Fujita scale -- with winds of 110 mph, according to the weather service.
Carl Brewer, the mayor of Wichita, told Fox News that the city was hit harder by high winds and golf ball-sized hail than anything from the tornado.
"That alone, and the rain, actually just really did a number on the city," he said. "It was so bad you think a tornado came through."
Brewer said hail ripped through the sides of houses in Wichita, in addition to breaking windows and damaging cars.
Jim Raulston, of Wichita, said the ferocious winds slammed the hailstones into his home.
"It was just unbelievable how the hail and everything was just coming straight sideways," Raulston said.
The National Weather Service also reported two tornadoes touched down in Iowa Sunday — near Huxley and Earlham. Damage included the loss of some cattle when the storm blew over a barn on a farm in Mitchell County. Some 11,000 homes were without power early Monday.