JOPLIN, Mo. - Rescue and recovery work in Joplin was shadowed by uncertainty Wednesday as crews still hoping to find survivors combed areas that had already been searched several times and engineers entered the battered Joplin hospital where the tornado killed five to see if it could be salvaged.
The death toll has reached at least 122, with 750 people hurt, from a mighty twister that the National Weather Service said was an EF5, the strongest rating assigned to tornadoes, with winds of more than 200 mph. But officials in the southwest Missouri city of 50,000 people say they still hope to find more survivors after two people were rescued from the rubble Tuesday, bringing the total to nine.
Even as Joplin limped forward, violent weather struck again, killing at least eight in Oklahoma, four in Arkansas and two more in Kansas. Late-night tornado sirens had Joplin's residents ducking for cover before the storm brushed past without serious problems.
Officials at St. John's Regional Medical Center sent structural engineers into the nine-story building hit squarely by the twister to see whether it could be saved.
"It's truly was like a bomb went off almost on every floor," chief executive Gary Pulsipher said.
Lynn Britton, president and chief executive of Sisters of Mercy Health Systems, praised the "heroic" efforts by staff and others who helped in the storm's aftermath and said a temporary hospital would be running near the site by Sunday. Patient information was safe after the hospital moved from paper to electronic records in May.
"We are still in a search-and-rescue mode," said Mark Rohr, Joplin's city manager. "I want to emphasize that."
Missy Epperson heads a team of 13 volunteers and rescue dogs from Illinois. She also searched for victims at World Trade Center after the Sept. 11, 2001, terror attacks and after Hurricane Katrina struck New Orleans in 2005.
"This is Katrina without the water," Epperson told CBS News correspondent Don Teague.
One difficulty in the search-and-rescue operation was summarized in an interview CBS "Early Show" co-anchor Chris Wragge had with one of a 50-man special search-and-rescue team in Joplin.
"Everybody's accounted for in the building, but who knows who was in front of the building," one member of St. Louis County's Strike Team Three told Wragge outside one wrecked structure.
Social networks were the tool of choice for many people trying to track the missing or to let their loved ones know they were OK.
Several online efforts have focused on Will Norton, a teenager who vanished on his way home from his high school graduation ceremony. Norton was driving with his father, Mark Norton, when the storm hit his Hummer H3. The vehicle flipped several times, and Will was thrown from it, likely through the sunroof.
Sara Norton was on the phone with her father as the two drove home. Mark Norton asked her to open the family's garage door so Mark and Will could get inside quickly. But the two never made it.
"I could hear him saying, 'Will, pull over, pull over,'" Sara Norton said.
Mark Norton tried to grab his son, but the storm was too strong. He was hospitalized Tuesday, seriously hurt but still able to talk to his family about what happened.
Will's sister, Sara Norton, and other relatives drove to hospitals throughout Missouri to search for Will. More than 19,000 people supported the "Help Find Will Norton" community page on Facebook, and Twitter users were tweeting heavily about the missing teen.
"I just want to find him, that's all," Sara Norton said Tuesday, on her way home from a Springfield, Mo., hospital. "I'm just determined. I have to find him."
Joplin schools were ravaged by the twister and classes have been canceled for the rest of the school year, but district officials are trying to locate both faculty and many of the school's 2,200 students. The effort has been crippled by downed phone lines. Some students have been located using Facebook.
"We just want to be able to find who we can find and then as confirmation happens offer support to the families if we find out that a kid didn't make it," Joplin High Principal Kerry Sachetta said.
At the same time, some attention has turned to the future. School officials have vowed to be ready for classes to start as scheduled on Aug. 17, despite having four schools destroyed and an estimated $100 million in damage. Superintendent C.J. Huff said the district is taking inventory to determine which buildings can be used and talking to other districts about possibly having Joplin students attend their schools.
The Joplin tornado was the deadliest single twister since the weather service began keeping official records in 1950 and the eighth-deadliest in U.S. history. Scientists said it appeared to be a rare "multivortex" tornado, with two or more small and intense centers of rotation orbiting the larger funnel.
Bill Davis, the lead forecaster on a National Weather Service survey team, said he would need to look at video to try to confirm that. But he said the strength of the tornado was evident from the many stout buildings that were damaged: St. John's Regional Medical Center, Franklin Technology Center, a bank gone except for its vault, a Pepsi bottling plant and "numerous, and I underscore numerous, well-built residential homes that were basically leveled."
Davis' first thought on arriving in town to do the survey, he said, was: "Where do you start?"