A fast-moving storm system triggered multiple tornadoes on Sunday that killed at least six people and flattened large parts of a town in Illinois as it tore across the Midwest, authorities said.
The tornadoes leveled scores of homes and demolished entire neighborhoods. Some 80 tornado reports were received, along with 358 reports of damaging winds and 40 reports of large hail, according to Rich Thompson, a lead forecaster with the weather service's Storm Prediction Center in Norman, Oklahoma.
Traffic was halted briefly at Chicago's two major airports, and tens of thousands of people in several states lost power.
By early Monday three people were reported killed in Massac County, two in Washington County and one in the city of Washington, in Tazewell County, said Patti Thompson of the Illinois Emergency Management Agency.
The National Weather Service confirmed preliminary EF-4 tornado damage in Washington County in southern Illinois, with winds of 166 to 200 miles (267-322 km) per hour.
The unusual late-season storms moved dangerously fast, tracking east at 60 miles per hour (97 kph), with the bulk of the damage spanning about five hours, Thompson said. Wind damage threats continued across Pennsylvania and New York.
The town of Washington, 145 miles (233 km) southwest of Chicago, was hit hard as tornadoes tore through Indiana and Kentucky, Illinois and a small corner of Ohio.
"The devastation is just unbelievable," said Mayor Gary Manier. Hundreds of homes were destroyed, one person was killed and 31 were being treated for injuries in nearby Peoria.
"I can't imagine people walked away from these places," Manier said of the devastation in the town of 15,000.
Two people, an 80-year-old man and his 78-year-old sister, were killed in Washington County, Illinois, about 200 miles (320 km) south of Peoria, County coroner Mark Styninger said.
Three others were killed in Massac County, Illinois, on the Kentucky border where a tornado devastated several neighborhoods, emergency officials said.
Sara Sparkman, a spokeswoman for the Tazewell County, Illinois health department, told Reuters: "We have reports of homes being flattened, roofs being torn off ... We have actual whole neighborhoods being demolished by the storm."
More people were feared trapped in their basements under debris, said Illinois State Police spokeswoman Monique Bond.
The American Red Cross worked with emergency management officials to set up shelters and provide assistance.
The Washington tornado came out of a fast-moving system that originally headed toward Chicago, forcing a delay of a Chicago Bears-Baltimore Ravens NFL game as it threatened a large swath of the Midwest.