Weather officials said the twister that struck the city of 50,000 at dinner time on Sunday was the deadliest single tornado in the United States since 1947 and the ninth-deadliest tornado of all time.

Authorities on Monday put the casualty toll at 116 dead and some 400 people hurt, many suffering severe internal injuries.

Seven people trapped by the storm had been rescued, Missouri Governor Jay Nixon told reporters in Joplin. Emergency crews searched through the night and through a thunderstorm with driving rain on Monday for additional survivors.

"We still believe there are folks alive under the rubble, and we're trying hard to reach them," Nixon said.

Survivors told harrowing stories of seeking shelter from winds of nearly 200 miles per hour in walk-in coolers in restaurants and convenience stores, hiding in bathtubs and closets, and of running for their lives as the tornado neared.

"We were getting hit by rocks, and I don't even know what hit me," said Leslie Swatosh, 22, who huddled on the floor of a liquor store with several others clutching one another as they prayed. When the tornado passed, the store was destroyed but those inside were all alive.

"Everyone in that store was blessed. There was nothing of that store left," she said.

More severe storms were predicted for the region, in a year that has brought tornadoes of record intensity across several states. Further complicating the rescue effort, power lines were downed, broken gas lines ignited fires, and cell phone communications were spotty due to 17 toppled phone towers.

A number of bodies were found along the city's "restaurant row," on the main commercial street, and a local nursing home took a direct hit, said Newton County Coroner Mark Bridges.

Roaring along a path nearly six miles long and about 1/2 mile to 3/4 mile wide, the tornado flattened whole neighborhoods, splintered trees and flipped over cars and trucks. Some 2,000 homes and many other businesses, schools and other buildings were destroyed.

At St John's hospital 180 patients cowered as the fierce winds blew out windows and pulled off the roof. According to AccuWeather.com Senior Meteorologist Alan Reppert, X-ray films from the hospital were found 70 miles away.

Six of the confirmed fatalities occurred at the hospital said Joanne Cox, a spokeswoman for the facility. Five were intensive-care patients who were on ventilators that lost power when the tornado struck, Cox said. The sixth was a visitor, but the circumstances of that death were unclear.

20 MINUTES NOTICE

The city's residents were given about 20 minutes' notice when 25 warning sirens sounded Sunday evening, said Jasper County Emergency Management Director Keith Stammers.

Nixon said many people may have been unable to reach shelter in time. "The bottom line was the storm was so loud you probably couldn't hear the sirens going off." He declared a state of emergency and called out the National Guard to help.

An estimated 20,000 homes and businesses were without power in Joplin.

The Joplin tornado was the latest in a string of powerful twisters that has wreaked death and devastation across numerous states, and it comes as much of the Mississippi River Valley is underwater from massive flooding.

Twisters killed more than 300 people and caused more than $2 billion in property damage across Southern states last month, killing more than 200 in Alabama alone.

The death toll of at least 116 topped the 115 people who perished in a 1953 tornado in Flint, Michigan. A 1947 tornado in Woodland, Oklahoma, killed 181 people.

Joplin City Councilwoman Melodee Colbert-Kean, who serves as vice mayor, said the town was in a state of "chaos."

"It is just utter devastation anywhere you look to the south and the east -- businesses, apartment complexes, houses, cars, trees, schools ... it is leveled, leveled," she said.

Survivors spent much of Monday sifting through rubble and debris for what was left of their possessions. Access to many neighborhoods remained blocked by wreckage or by search teams.

Jeremy Ball, 38, was able to get into his home only by crawling through a window. He recalled Sunday night's terror, when he helped search nearby homes and found the bodies of a woman neighbor and her 15-year-old daughter.

"That is something you never want to have to do," he said.