MSNBC.com says six people were killed by an apparent tornado in Harrisburg, Illinois, early today.
The other deaths include three in Missouri and one in Oklahoma.
In Stoddard County, Missouri, two people found thrown from a mobile home during a storm died after being airlifted to a Cape Girardeau hospital. The other Missouri death happened as a twister ripped through a trailer park in Buffalo, in southwest Missouri.
At least one person was killed when a tornado slammed into the town of Tushka, Oklahoma, about 135 miles south of Tulsa.
At least 13 people are injured in Buffalo, Missouri, Dallas County Emergency Management Director Jason Wendlandt tells KARK sister station KOLR10 News there is one confirmed death south of Buffalo from the storm overnight.
Wendlandt says the death happened near Highway F and South Ash, the center of the worst damage about 2 miles south of Buffalo. Health rescue crews are also confirming a number of injuries in Dallas County, Missouri.
Some of the worst damage is in towns such as Branson, Missouri and Harveyville, Kansas.
Kansas Governor Sam Brownback has issued a state of emergency for Wabaunsee County where Harveyville is located.
Local emergency officials in Branson say the storms damaged some of the town's famed music theaters as well as a Walmart, a Taco Bell, a pizza shop and at least one hotel.
In Arkansas, Sharp County dispatchers tell KARK their officers are seeing debris around several of their roads and highways, specifically in Cherokee Village, and residents have reported hail around Hardy and Martin Creek.
No tornado sightings have been reported in Arkansas so far, though many have been reported in Missouri. It's still too early for any to be confirmed.
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