A tornado ripped apart the roof of an elementary school, damaged house roofs, smashed trees and toppled power lines when it struck the southeastern Wisconsin community of Hartford Sunday afternoon.

There were no reports of serious injuries from the storm that left debris strewn around the area where the twister hit in this city of 8,200 people located 25 miles northwest of Milwaukee.

The National Weather Service said in a preliminary storm report that the tornado struck at 2:44 p.m. and caused part of the roof and a wall of the Silver Belle Motel to collapse and also damaged the roof of Lincoln Elementary School.

Reporters at the scene said people were immediately pitching in to help with cleanup work. At a custard stand that lost electric service, free custard was being passed out to passersby.

The weather service gave the storm a preliminary rating of F1 on the Fujita scale for measuring the strength of tornadoes, which means it had winds from 73 to 112 mph.

The storm knocked out power to 143 customers in the Hartford area, said We Energies spokeswoman Wendy Parks. She said crews were making repairs Sunday evening, and people were being advised to stay away from any downed lines and report them to the utility.

Elsewhere, there were numerous reports of funnel clouds across southeastern Dane County as severe thunderstorms developed in southern Wisconsin, the weather service said.

Other warnings were posted for Rock, Dodge, Washington and parts of Jefferson counties because of the possibility of tornadoes, but the warnings expired by later in the afternoon.

A possible tornado was spotted about 12 miles northwest of Milton moving east at 10 mph about a half hour after the Hartford one hit, weather officials said.