At least 12 people were killed after devastating tornadoes and storms steamrolled through the Midwest and South. NBC's Lester Holt and TODAY's Al Roker report.
Updated at 8:45 p.m. ET: HARRISBURG, Ill. -- At least 12 people were killed -- including several crushed by debris -- as tornadoes marched across the Midwest, flattening parts of several towns including the tourist hub of Branson, Mo.
Hardest hit was Harrisburg, where four women and two men died, some 100 others were injured and more than 200 homes were destroyed or damaged.
Most if not all the Harrisburg dead were killed by a home tossed atop their own property early Wednesday, a witness said.
Whitney Curtis / Getty Images
Steve McDonald stands among debris from the home of his mother-in-law, Mary Osman, who was killed in the twister that raced through Harrisburg, Ill.
"It's a house on top of a house," said Mike Hancock, 29, who with several others tried to rescue the victims. "We crawled in there as much as we could. Then there wasn't enough stability, the whole foundation was shaking. We had to get out of there," he said.
"We have devastation in our community like we've never seen," Mayor Eric Gregg told a press conference, where officials said the twister had peak winds of 170 mph, making it an EF-4 on the 1-5 scale used by the National Weather Service, with 5 being the most severe.
"There are hundreds of homes damaged, millions of dollars in damage," he added. "The hospital is severely damaged. There's a mall with 10 stores that was destroyed."
Forecasters warned more twisters could strike the Tennessee Valley and southern Appalachians through Wednesday evening as the storm system moved east.
Rock Center reports on the aftermath of the powerful tornadoes that ripped through America's heartland, killing at least nine people. The twisters blew houses on top of each other and toppled buildings as they hopscotched through parts of Missouri, Illinois and Kansas. NBC's Lester Holt and The Weather Channel's Jim Cantore report from Harrisburg, Ill., one of the towns hit hardest by the tornadoes.
Three other deaths were reported in Missouri, where a suspected tornado hit a mobile home park outside the town of Buffalo. One person died there and around a dozen people were injured. Two others died in the Cassville and Puxico areas of Missouri, state officials said. Three deaths were reported in eastern Tennessee, The Associated Press reported.
In Harrisburg, police issued a curfew overnight and the area most impacted was evacuated as a precaution. Some 3,300 customers were without power in the town of about 10,000.
In Kansas, 12 people were injured when a EF-2 tornado made a five-mile-long run through Harveyville on Tuesday night, officials said. Three of the injured were in critical condition, and 40 percent of the town suffered damage.
NBC affiliate KSHB TV reported that an apartment complex and a church were among the damaged buildings in the town of about 250 people.
Kansas Gov. Sam Brownback issued a disaster declaration for the area, parts of which were without power.
NBC's Al Roker reports on the unseasonable tornadoes that ripped through Illinois.
Other hard-hit areas included Branson and Lebanon in Missouri.
In Branson, 32 people were treated at one hospital for injuries, mostly cuts and bruises. A tornado moved through downtown overnight, heavily damaging the city's famous theaters and hopscotching up Highway 76, uprooting road signs and scattering debris.
Officials on Wednesday gave the tornado a preliminary rating of EF-2 and said it ran an 8- to 10-mile path.
The injuries could have been far worse had the storm hit next week, when the tourist season picks up.
"If it was a week later, it'd be a different story," said Bill Tirone, assistant general manager for the 530-room Hilton and adjacent Branson Convention Center, where windows were shattered and some rooms had furniture sucked away by high winds. Hotel workers were able to get all guests to safety as the storm raged.
Mark Schiefelbein / AP
Storm debris is piled near the entrance to the Dick Clark's American Bandstand Theater in Branson, Mo., on Wednesday.
John Moore, owner of the damaged Cakes-n-Creams '50s Diner, said the apparent twister appeared to "jump side to side" as it moved down the entertainment district, right through the convention center, across a lake and into a housing division.
"The theater next to me kind of exploded. It went everywhere. The hotels on the two sides of me lost their roofs. Power lines are down. Windows are blown out," Moore said. "There's major, major destruction. There has to be millions dollars of damage all down the strip."
Jennifer Verhaalen said she saw a white funnel cloud followed by a wall of rain as the storm closed in on the town around 1 a.m.
She said she retreated to a back bedroom with her husband as the storm slammed into two hotel buildings, tearing the roof off one.
Across the road, a strip mall lay in tatters, its roof missing and several walls collapsed.
Branson has long been a touristy outdoor destination for visitors who came to see the beauty of the surrounding Ozarks. But the city rose to prominence in the 1990s largely due to the theater district, where venues featured the star power of country music and celebrities including the Osmonds and Andy Williams.
John Hanna / AP
Damage in Harveyville, Kan., includes this home.
In Lebanon, a tornado was reported at 12:25 a.m. and numerous reports came in of damage in the area. A tractor-trailer was reported to have been blown off Interstate 44 nearby.
Newburgh, Ind., also saw damage from severe storms. Several homes and a business were hit, though no injuries or deaths were reported.
The National Weather Service said it was forecasting more tornadoes on Wednesday, including "one or two possibly strong" ones as well as "damaging wind over parts of the Tennessee Valley to southern Appalachians" into the evening.
The system also skirted northern Arkansas, bringing gusts of up to 60 miles per hour in the northwest. A wall cloud was reported in Cherokee Village, where trees were scattered along roads, the weather service said. Residents of Clay County in northeastern Arkansas reported hail the size of golf balls, and similar-sized hail was reported in Mountain Home.
Mathew Fowler / Harveyville Gazette via AP
Damage is seen Wednesday morning in Harveyville, Kan., after an apparent tornado passed through Tuesday night.
In northern Oklahoma, gusts of up to 80 mph flipped trailers and damaged homes near Cherokee.
Tornado season normally starts in March, but it isn't unusual to see severe storms earlier in the year. Forecasters have a particularly difficult time assessing how serious a season will be in part because tornadoes are so unpredictable. This year, two people were killed by separate tornadoes in Alabama in January, and preliminary reports show 95 tornadoes struck that month.
NBC News, Reuters and The Associated Press contributed to this report.
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