HARRISBURG, Ill. • With the walls torn off three rooms by a powerful tornado Wednesday morning and the windows blown out of four others, the worst was yet to come for this small city’s hospital.

Among the scores of injured neighbors who hobbled or were wheeled in, four were dead. And one of the dead was a young nurse from the staff, pulled by rescuers from her shattered apartment.

“You had nurses here facing lots and lots of trauma in a building that had been damaged and they had lost one of their own,” explained Vince Ashley, chief executive of the Harrisburg Medical Center.

“It was dark and wet and everything you can imagine all at once,” he said as some equilibrium was returning to his tattered building, where glass littered the floor and wires hung from ceilings.

Whole neighborhoods were flattened in this community of 9,000 people, about 100 miles southeast of St. Louis. Six people were killed here as at least 16 tornadoes swept from Nebraska to Kentucky.

Missouri counted three dead, in Buffalo and the Cassville and Puxico areas. Officials said at least 37 people suffered mostly minor injuries in Branson, where hotels and some of its famous theaters were damaged just days before start of the tourism season.

The Harrisburg twister was an E4, the second strongest category, National Weather Service Rick Shanklin deduced from the damage. He said it scoured a path about 200 yards wide with wind up to 170 mph, splintering buildings and tossing vehicles like toys.

It moved through the Country Club Hills subdivision so quickly that Dr. Vinay Mehta never had a chance to leave his upstairs bedroom. “It came so fast, and then it was gone,” he said. “It lasted no more than 30 seconds.”

Mehta ventured outside, where power lines crackled and many of his neighbors’ homes were destroyed. The surgeon walked a few blocks to the hospital and treated a lot of broken bones. Other patients were airlifted out, he said, noting, “Some of them had serious problems.”

Storm spotters gave Harrisburg about 30 minutes of warning before the tornado cut a swath across the southern part of the city just before 5 a.m.

Forewarned, the medical center moved patients away from vulnerable areas. Afterward, it transferred out the patients it could while dealing with a flood of incoming injuries. Ashley said none of the 12 patients in the damaged unit was hurt.

Saline County Sheriff’s Lt. Tracy Felty estimated about 100 people were injured. No one was believed to be missing.

The death toll here had been reported as high as 10, but that was the result of a misunderstanding, said, Patti Thompson, spokesperson for the Illinois Emergency Management Agency. “We were given some incorrect information,” she said. “Things are pretty hectic down there.”

Officials did not release names of the dead — four women and two men.

Estimates said that up to 300 homes and 25 businesses were damaged or destroyed. Southeastern Illinois College announced it would be closed through the end of spring break, March 12, to deal with damage.

“We have devastation in our community like we’ve never seen,” Mayor Eric Gregg said in a briefing Wednesday afternoon. “We can deal with floods. We can deal with lots of things but dealing with a tornado is heartbreaking.”

One resident, Darrell Osman said he arrived at his dying mother’s home in time to speak to her before she was taken away with a head injury, a severe cut to her neck and a broken arm and leg. “She was conscious. I wouldn’t say she was coherent. There were more mumbles than anything,” he said. “She knew we were there.”

Back in Country Club Hills, a hard-hit area, Karen McClusky said she emerged from hiding in her bathtub to see if her house was still there; it was.

“I then went and checked on my neighbors and saw whole houses destroyed,” said McClusky, an eighth grade social studies teacher who had lived in the neighborhood for 27 years.

As she spoke, the area already banged and buzzed with the sounds of workers wielding hammers and chain saws. Some residents walked the streets to stare, take pictures or share embraces.

Sherry Chrisman looked at what was left of her home and said it will have to be bulldozed. “I cater, and this is my kitchen,” she said pointing to the remains of some walls and her back yard swimming pool.

Chrisman had gotten up to cook just before the storm hit. She, her daughter and a golden retriever named Mable took refuge in the basement. “The puppy was just going nuts,” she said.

“The noise wasn’t that bad, it was the pressure,” Chrisman said. “My ears really hurt and I could just feel tremendous pressure.”

They had to wait for rescuers to help get them out of the rubble.

“I haven’t cried once, she told a reporter. “Not yet.”

The Red Cross set up a shelter for the displaced at the First Baptist Church, 204 North Main Street.

Police asked that sightseers stay away, and announced a 6 p.m. to 6 a.m. curfew in the stricken areas to prevent looting.

Hundreds of Ameren workers were converging from Metro East and Missouri to restore electricity. The utility said outages for more than 14,200 customers were whittled to about 3,300 by Wednesday, with full service expected by Friday.

Gov. Pat Quinn toured the scene Wednesday afternoon and said he was declaring it a disaster area to provide eligibility for assistance.

Other serious damage was reported in that general area, including destruction of the St. Joseph Church in Ridgway, Ill.

The immediate St. Louis area experienced heavy winds that downed some power lines and broke some tree limbs on Wednesday morning, but no injuries were reported. DePaul Health Center in Bridgeton lost power and had to run on backup generators. The weather service reported the highest wind at 52 mph at 2:15 a.m. in the Harvester area of St. Charles County.

As the region’s damaged communities dug out, the Storm Prediction Center, in Norman, Okla., forecast another potentially damaging system Friday that meteorologist Ryan Jewell said would put the Midwest and South “right in the bull’s eye.”

Kim Bell, Kevin McDermott and Joel Currier of the Post-Dispatch, the Associated Press and the Southern Illinoisan contributed to this report.