At least six people were killed in tornadoes in Iowa on Saturday.
Local disaster response chief Diogenes Ayala reported the dead in Madison County, southwest of Iowa's capital Des Moines, according to ABC's Local 5 News and other media outlets.
At least four other people were seriously injured.
Two children under the age of five were among the dead, Ayala said.
According to reports, several tornadoes raged around Des Moines on Saturday afternoon and evening, damaging or destroying homes and cars between the towns of Winterset in Madison County and Newton in Japser County.
Thousands of people were temporarily without power.
Iowa Governor Kim Reynolds declared Madison County a state of emergency.
This means government funds can be used for rescue and salvage operations, a statement said.
"Our hearts go out to all those affected by the deadly storms," she wrote.
According to the US broadcaster CNN, severe storms usually hit the states on the Gulf Coast, i.e. between Texas and Florida, in March.
Iowa typically only gets two tornadoes in March, while Texas, for example, experiences an average of 11, CNN wrote on its website.