MILWAUKEE, Wis. -

Milwaukee police are investigating a single-vehicle crash that killed two people, along with a pair of apparently unrelated shootings that left one teen dead and a man injured.

The police department said the car crash happened Saturday about 12:45 a.m. Officers said the occupants were a 49-year-old Milwaukee man and an unidentified man. Both were killed, and police say speed and alcohol are believed to be factors.

The first of the two shootings happened Friday shortly before midnight. A 17-year-old Greenfield boy was shot and killed as he sat in a vehicle.

The other shooting happened two hours later. A 26-year-old Milwaukee man who was also sitting in a vehicle was shot in the leg.

Police have no suspects in either shooting.