Updated

A helicopter crashed into the roof of a house early Sunday, killing two people in the aircraft, but five people in the house were uninjured, police reported.

The helicopter crashed around 5:30 a.m., about one mile south of the Kenosha Airport, police Sgt. Eric Larsen said.

Fog was reported in the area at the time, but there was no immediate indication if that played a role in the crash. Visibility at 5:30 a.m. was three-quarters of a mile to a mile, National Weather Service meteorologist Chris Franks said.

Gary Stielow, who lives about 100 yards from the crash site, said he woke up and heard the helicopter before it crashed.

"The engine just didn't sound right," Stielow told the Milwaukee Journal Sentinel. "It was sputtering. It was at full power, but it was sputtering real bad. Then you just heard a loud boom."

Stielow said he ran outside and saw that the family in the house had made it out safely. The bodies of the two people killed in the crash were on the ground next to the helicopter's engine, which was on fire, Stielow said.

Federal Aviation Administration spokesman Tony Molinaro said the helicopter was a 2006 Robinson R-44 registered to Midwestern Air Services of Kenosha, which provides charter services and flight training.

Molinaro said the pilot did not appear to have filed a flight plan. The airport's tower does not open until 7 a.m., so travel earlier than that is "at your own risk," said Corey Reed, operations supervisor at the airport.

A preliminary report on the crash will take about a week to complete, said Ed Malinowski, an air safety inspector for the National Transportation Safety Board. He said he did not think the helicopter had a flight data recorder.

A phone listing for Midwestern Air Services could not immediately be found.