A powerful tornado killed seven people, including two young children, and injured six others in Iowa on Saturday night, officials said.
The apparent twister in Madison County, Iowa, was not yet confirmed by the National Weather Service, but federal forecasters said images from the damage suggest it was at least a EF3 tornado, which would put minimum-force winds at 158 mph.
Search and rescue efforts were paused for the evening, and volunteers were asked to show up in the morning to help determine if more are dead or injured, Diogenes Ayala, director of the Madison County Emergency Management Agency said at a news conference late Saturday.
"This is worst tornado damage I’ve seen in Madison county, worst anyone has seen in quite a long time," Ayala said.
Iowa Gov. Kim Reynolds late Saturday issued a disaster proclamation for the county, saying it could free up state funds for response and recovery.
“Our hearts go out to all those affected by the deadly storms that tore through our state today,” Reynolds said in a statement. “ ... Our hearts ache during this time, but I know Iowans will step up and come together to help in this time of need—they already are.”
She said declarations may be needed for other counties as damage assessments continue.
Officials believe as many as 30 homes may have been destroyed by the tornado, which was described as causing widespread damage in the county. National Weather Service officials were expected to go to the site Sunday to confirm the touch down and determine its force.
Four adults were hospitalized, three with serious injuries and one with life-threatening injuries, the emergency management agency said.
In nearby Lucas County, Emergency Management Coordinator Mike Lamb told NBC News that one person had been killed and another seriously injured. A handful of people suffered minor injuries, he said.
He added that trees and powerlines had come down and there was “significant utility damage.”
Two people were also injured in Polk County, Dutch Geisinger, the deputy director of the of the county's Emergency Management Agency said in a release.
He added that "downed powerlines, standing water and debris" were blocking roadways and creating dangerous travel conditions.
The damage following the 4:30 p.m. storm appeared to be centered on a road roughly 45 miles south-southwest of Des Moines, officials said.
The unsettled air moved across the area Saturday night as a result of a series of storms throughout the Midwest, the flip side of a cold front to the north.
The Weather Service had warned of severe weather across south-central Iowa and northern Missouri, including damaging wind gusts, isolated tornadoes, and large hail.
The apparent tornado and high winds may have also caused downed lines and branches that presented traffic hazards and blocked traffic in the region.
More than 6,200 utility customers in Iowa were without power Saturday night.