US Authorities say at least seven people have been killed in tornados and thunderstorms that swept through Illinois, Ohio and Michigan.

50 homes were destroyed and scores more damaged. Several people were taken to hospital. No one has been reported missing.

The storm left a 13-kilometer path of destruction. An official says the field house at local high school was damaged and the cafeteria was destroyed.

The winds were so powerful they tossed buses across the school parking lot.