Massive tornado kills at least 116 in Joplin, Mo.

JOPLIN, Mo. – Rescue crews dug through piles of splintered houses and crushed cars Monday in a search for victims of a half-mile-wide tornado that killed at least 116 people when it blasted much of this Missouri town off the map and slammed straight into its hospital.

It was the nation’s deadliest single twister in nearly 60 years and the second major tornado disaster in less than a month.

Authorities feared the toll could rise as the full scope of the destruction comes into view: house after house reduced to slabs, cars crushed like soda cans, shaken residents roaming streets in search of missing family members. And the danger was by no means over. Fires from gas leaks burned across town, and more violent weather loomed, including the threat of hail, high winds and even more tornadoes.

At daybreak, the city’s south side emerged from darkness as a barren, smoky wasteland.

“I’ve never seen such devastation – just block upon block upon block of homes just completely gone,” said former state legislator Gary Burton, who showed up to help at a volunteer center at Missouri Southern State University.

Unlike the multiple storms that killed more than 300 people last month across the South, Joplin was smashed by just one exceptionally powerful tornado.

Not since a June 1953 tornado in Flint, Mich., had a single twister been so deadly. That storm also killed 116, according to the National Weather Service.

Authorities were prepared to find more bodies in the rubble throughout this gritty, blue-collar town of 50,000 people about 160 miles south of Kansas City.

Gov. Jay Nixon told the Associated Press he did not want to guess how high the death toll would eventually climb. But he said: “Clearly, it’s on its way up.”

Seventeen people were pulled alive from the rubble. An unknown number of people were hurt.

While many residents had up to 17 minutes of warning, rain and hail may have drowned out the sirens.

Larry Bruffy said he heard the first warning but looked out from his garage and saw nothing. “Five minutes later, the second warning went off,” he said. “By the time we tried to get under the house, it already went over us.”

As rescuers toiled in the debris, a strong thunderstorm lashed the crippled city. Rescue crews had to move gingerly around downed power lines and jagged chunks of debris as they hunted for victims and hoped for survivors. Fires, gas fumes and unstable buildings posed constant threats.

Teams of searchers fanned out in waves across several square miles. The groups went door to door, making quick checks of property that in many places had been stripped to their foundations or had walls collapse.

National Weather Service Director Jack Hayes said the storm was given a preliminary label as an EF4 – the second-highest rating assigned to twisters based on the damage they cause.

Hayes said the storm had winds of 190 to 198 mph. At times, it was three-quarters of a mile wide.

Some of the most startling damage was at St. John’s Regional Medical Center, where staff had only moments to hustle their patients into the hallway. Six people died there, five of them patients, plus one visitor.

The storm blew out hundreds of windows and caused damage so extensive that doctors had to abandon the hospital soon after the twister passed. A crumpled helicopter lay on its side in the parking lot near a single twisted mass of metal that used to be cars.

Dr. Jim Riscoe said some members of his emergency room staff showed up after the tornado with injuries of their own, but they worked through the night anyway.

Once the center of a thriving mining industry, Joplin flourished though World War II because of its rich lead and zinc mines.

The community is now a transportation crossroads and manufacturing hub.

As the tornado bore down on their trailer home, Joshua Wohlford, his pregnant girlfriend and their two toddlers fled to a Walmart store. The family narrowly escaped after a shelf of toys partially collapsed, forming a makeshift tent that shielded them.

“It was 15 minutes of hell,” Wohlford said.

At a Fast Trip convenience store, another 20 people ran into a pitch-black cooler as the building began to collapse around them. They documented their experience with a video that was drawing tens of thousands of views online by Monday afternoon. The audio was even more terrifying than the imagery – earsplitting wind, objects smashing, wailing children and a woman praying repeatedly.

Brennan Stebbins said the group crouched on the floor, clinging to and comforting each other until they were able to crawl out. No one was seriously hurt.

Shielded by mattresses, former lawmaker Chuck Surface rode out the storm in his basement with his wife, daughter, granddaughter and dog. After about five minutes, the deafening roar abruptly stopped.

“When it got to where we thought we could look out,” he said, “we went to the top of the stairs and there was no roof – it was all open air.”

Dazed survivors tried to salvage clothes, furniture, family photos and financial records from their flattened or badly damaged homes.

Kelley Fritz rummaged briefly through what was left of a storage building, then gave up. Her boys rushed into the neighborhood after realizing every home was destroyed.

When they returned, she said, “my sons had deceased children in their arms.”

Forecasters said severe weather would probably persist all week. Arkansas, Kansas, Missouri and Oklahoma could see tornadoes through today, and the bad weather could reach the East Coast by Friday.

The twister that hit Joplin was one of more than 50 reported across seven Midwest states over the weekend. One person was killed in Minneapolis and another in Kansas, but Missouri took the hardest hits.