Children among the at least 51 dead after massive twister strikes near Oklahoma City A massive tornado at least a half mile-wide with 200 mph winds churned through Oklahoma City's suburbs Monday afternoon, killing at least 51 people including at least 20 children, flattening entire neighborhoods and destroying an elementary school with a direct blow as children and teachers huddled inside. Amy Elliott, a spokeswoman for the Oklahoma Medical Examiner's Office, said early Tuesday 51 people were confirmed dead, at least twenty of them children.She said officials could see as many as 40 more fatalities from the tornado. The storm laid waste to scores of buildings in Moore, a community of 41,000 people about 10 miles south of Oklahoma City. Block after block lay in ruins. Homes were crushed into piles of broken wood. Cars and trucks were left crumpled on the roadside. More than 120 people were being treated at hospitals, including about 50 children. Search and rescue crews were looking for anyone who may be trapped in the rubble. Many land lines to stricken areas were down, and cell phone networks were congested. The storm was so massive that it will take time to establish communications between rescuers and state officials, Oklahoma Gov. Mary Fallin said. Fallin deployed 80 National Guard members to assist with rescue operations and activated extra highway patrol officers. She also spoke with President BObama, who declared a major disaster and ordered federal aid to supplement state and local recovery efforts. James Rushing, who lives across the street from the school, heard reports of the approaching twister 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. The students were sent into the restroom. A man with a megaphone stood near a Catholic church Monday evening and called out the names of surviving children. Parents waited nearby, hoping to hear their sons' and daughters' names. Don Denton hadn't heard from his two sons since the tornado hit the town, but the man who has endured six back surgeries and walks with a severe limp said he walked about two miles as he searched for them. As reports of the storm came in, Denton's 16-year-old texted him, telling him to call. "I was trying to call him, and I couldn't get through," Denton said. Eventually, Denton said, his sons spotted him in the crowd. They were fine, but upset to hear that their grandparents' home was destroyed. As dusk began to fall, heavy equipment was rolled up to the school, and emergency workers wearing yellow crawled among the ruins, searching for survivors. Because the ground was muddy, bulldozers and front-end loaders were getting stuck. Crews used jackhammers and sledgehammers to tear away concrete, and chunks were being thrown to the side as the workers dug. OU Medical Center spokesman Scott Coppenbarger said the hospital and a nearby children's hospital are treating approximately 85 patients, including 65 children, with conditions ranging from minor injuries to critical. Integris Southwest Medical Center spokeswoman Brooke Cayot said 9 of 57 patients being treated at that facility Monday are listed in critical condition. Nineteen are in serious and 29 others are listed in fair or good condition. Cayot said five of the patients at Integris are children, including two who came from the Plaza Towers Elementary School. 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. Briarwood Elementary School in Moore, one of two schools hit, suffered "extensive damage," according to Gary Knight with the Oklahoma City Police Department. 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. While the tornado was passing over the school, students were hugging and clinging to the walls, KFOR reports. Children from the school were among the dead, but several students were pulled alive from the rubble. Rescue workers passed the survivors down a human chain to the triage center in the parking lot. A Norman, Oklahoma regional health system spokesperson also told Fox News that Moore Medical Center, the only hospital in the city, also suffered "extensive structural damage," as the tornado demolished the second floor of the hospital and tore off part of the roof. The center evacuated 30 patients to two other hospitals in Norman, Oklahoma. 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. In a statement, a spokesperson for FEMA said it is "closely monitoring the impacts of the storm and remains in close contact with emergency officials to ensure there are not any unmet needs." "Our thoughts and prayers go out to everyone impacted by the tornadoes and severe weather in Oklahoma," Secretary of Homeland Security Janet Napolitano said, urging residents to listen to the direction of state and local officials. 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. It's pretty bad. It's pretty much wiped out. Pottawatomie County Sheriff Mike Booth 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 ... 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. 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. 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. 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. Click for more from Fox 25.