JOPLIN, Mo. — Jonathan Elliott had heard the sirens blaring outside St. John's Regional Medical Center for nearly 30 minutes when things suddenly took a terrifying turn.
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The building started shaking, the lights began to flicker and 16-year-old Elliott could feel the wind coming up beneath the floor in his grandfather's seventh-floor hospital room. It was time to make a move, and that's what Elliott and his grandmother did, making a dash for the relative safety of an inside stairwell.
Up to that moment, "we had no idea it was going to blow," Elliott said.
The tornado that smashed Joplin on Sunday evening also ravaged one of the town's major hospitals just when it was needed the most, killing six people, blowing out windows and sucking up X-rays and medical records and dumping them two counties away.
After the twister had passed, the entire 367-bed hospital was evacuated for fear of structural damage to the modern, nine-story building, where walls were knocked 10 feet out of place and rooms strewn with broken glass, concrete, ceiling tiles and other dangerous debris. Some patients were taken out in wheelchairs, while others unable to make their way out on their own after the elevators were disabled were slid down the stairs on mattresses.
Doctors and nurses set up a triage center in the parking lot amid crushed cars and a smashed helicopter, but once the storm victims were evaluated, they had to be sent to other hospitals for treatment. Some staff members who reported to work at St. John's after the tornado were themselves injured but toiled through the night anyway.
At the time, the hospital had 183 patients. At least 59 of the St. John’s patients were taken to a sister hospital in Springfield, spokeswoman Lisa Cox said. The patients ranged in age from a 4-year-old boy to a 91-year-old woman, she said, adding that none of the patients' conditions has been confirmed.
At least 90 other patients were taken to CoxHealth hospitals in Springfield, said spokeswoman Stacy Fender. Many were treated and released and a few were admitted, said Fender, who couldn't comment on the patients' conditions.
The recovery effort was going as smoothly as possible, said Cox, of the St. John's site in Springfield. She credited frequent drills with calm amid the chaos.
"They really do a great job of preparing us for these kinds of incidents," she said.
'Looked like a nuclear disaster'
On the morning after the storm, parts of the hospital — one of Joplin's tallest buildings — appeared bombed out.
"I spent most of my life at that hospital," emergency room physician Dr. Jim Roscoe said, his voice cracking. "It's awful. I had two pregnant nurses who dove under gurneys. I had staff who showed up. They were hurt, but they worked all night long. It's a testimony to the human spirit."
In the terrifying minutes before the twister struck, the hospital declared a "Condition Gray," and patients, relatives and staff members were told to leave their rooms and go into stairwells and other protected interior parts of the building.
Despite what hospital officials said was at least 10 minutes' warning inside the building before the tornado hit, Roscoe said at least five of the 116 people who died in the tornado in Joplin were killed at St. John's. He said he did not know if the victims were patients or staff members.
He compared the carnage to what he saw in 1981 when he dealt with the collapse of a skywalk at the Hyatt Regency hotel in Kansas City, where 114 people were killed. He said it was also similar to the scene in Haiti last year when he went there to help after the earthquake.
"It looked like a nuclear disaster had happened. Cars had been thrown like playing cards. Power lines were sparking. I couldn't believe it," he said.
Grandfather survives with just a scratch
Elliott and his grandmother were among the fortunate. When they emerged from the stairwell, they didn't recognize the hospital.
The Wichita, Kan., teenager said that his grandfather had been taken off a ventilator earlier in the day. When the twister struck, Elliott said, he didn't have time to move the older man from his hospital bed and left him behind. When Elliott returned to the room, it was littered with debris, but his grandfather had suffered just one small scratch on his head.
"I was really worried, but I was really surprised," Elliott said.
While Elliott said he didn't hear the warning from the hospital staff to take cover, he said the doctors took control afterward, ordering everyone to evacuate the building as fast as possible. For the patients who couldn't walk, Elliott and others used mattresses to slide them down the stairs.
On the way out, Elliott saw at least three patients being given CPR. He also heard someone yell, "We've got a dead guy here!" on the third floor.
Officials said the hospital was completely evacuated within 90 minutes after the tornado. When Elliott finally emerged with his grandparents safe, he was shocked to see cars piled on top of one another. He looked back to see windows blown out, curtains whipping in the wind and bent pieces of metal covering the building.
"I was just trying to grasp it all," Elliott said.
The Associated Press and msnbc.com's Jonel Aleccia contributed to this report.