US tornadoes: Storm sweeps through America’s Midwest leaving at least six dead

A series of tornadoes sweeping across Illinois and Indiana have killed at least two people and injured at least 40 while flattening large parts of the city of Washington in Illinois (AP)

A series of tornadoes sweeping across Illinois and Indiana have killed at least six people and injured at least 40 while flattening large parts of the city of Washington in Illinois.

A fast moving storm has created multiple tornadoes in Bone Gap and Miller City, Illinois, in Mount Carmel, Noblesville and Vincennes in Indiana, and in Paducah, Kentucky, the National Weather Service said.

The storm also forced the American Football team, Chicago Bears, to halt their game against the Baltimore Ravens and encourage fans at Soldier Field to seek shelter as the storm roared in.

Chicago's two major airports also briefly stopped traffic with the metropolitan area was under a tornado watch.

The city of Washington, Illinois, was hit hard by what the National Weather Service called a "large and extremely dangerous" tornado.

An elderly man and his sister were killed when a tornado hit their farmhouse in the town of New Minden, in rural southern Illnois.

And one person was killed in Washington County, about 200 miles south of Peoria, where at least 70 homes were destroyed. Authorities confirmed three other people had also died.

"We have reports of homes being flattened, roofs being torn off," Sara Sparkman, a spokeswoman for the health department of Tazewell County, Illinois, where Washington is located, said in a telephone interview. "We have actual whole neighbourhoods being demolished by the storm."

Photos from Washington, Illinois, showed buildings reduced to rubble and homes torn in half in the city of 15,000 people some 145 miles southwest of Chicago.

Many of the injuries appeared to have been caused by the collapsing structures.

Illinois State Police spokeswoman Monique Bond said mobile homes were toppled, roofs torn from homes, and trees uprooted. She said officials believe some people may be trapped in their basements under debris.

The American Red Cross worked with emergency management officials to set up shelters and provide assistance to displaced residents, even as rescue workers searched for more people who might have been caught and trapped in the storm's path.

The Washington tornado came out of a fast-moving storm system that was headed toward Chicago and threatened a large swath of the Midwest with dangerous winds, thunderstorms and hail, US weather officials said.

"We obviously have a very dangerous situation on our hands," Laura Furgione, deputy director of the National Weather Service, told reporters on a conference call.

Weather officials urged residents of areas with tornado warnings in place to take cover in interior, low-floor rooms of study buildings.

The NWS's Storm Prediction Centre said the storm moved dangerously fast, tracking eastward at 60 miles per hour.

This storm system has some similarities to the fast-moving "derecho" storm that knocked out power to more than 4.2 million people and killed 22 in the Midwest and Mid-Atlantic regions in June 2012, according to Bill Bunting, forecast branch chief at the Storm Prediction Centre.

He said: "The line of storms today, we believe, when it's fully mature, will actually be larger than the areas that were affected by the derecho in June of 2012. However, this will also be accompanied by a worse tornado threat in the areas that we've highlighted and large hail in Illinois and Wisconsin."