DETROIT -- A pregnant woman is in a critical condition after being shot in the head while driving on an expressway in Detroit on Friday, myFOXdetroit.com reported.

The 18-year-old crashed the vehicle into a house on Detroit's west side after she was shot.

The passenger in the car, the woman's boyfriend, was uninjured and told myFOXdetroit.com the shot came from nowhere.

"We (were) on a freeway coming up on Wyoming exit. We (heard) two gun shots, and when we (heard) two gun shots, all I know is that I (looked) over to my left and I (saw) an arm hanging out the window of a white Pontiac," the 19-year-old said.

Detroit Police said the key to solving the crime would lie with anyone on the highway who may have witnessed the shooting.

"If there was a vehicle passing even in another direction or a little bit further up the road or down the road, if they might have seen something that could be of use to us, please call Detroit Police or call Crime Stoppers immediately," said John Roach with the Detroit Police Department.

The victim, who is three months pregnant, was taken to hospital, where she remains in a critical condition.

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