MILWAUKEE (CBS 58) -- Milwaukee police are investigating three separate shootings in four hours across the city Tuesday night, Dec. 21, 2021. 

The first shooting happened around 7 p.m. near W. Shea and National Ave.

A 33-year-old Milwaukee man sustained non-fatal injuries. The victim arrived at a local hospital for treatment. The circumstances leading up to the shooting are under investigation. Milwaukee police continue to seek unknown suspects. 

A second shooting happened around Tuesday, December 21, 2021, at approximately 9:40 p.m. near 10th and Concordia Ave.

A 21-year-old Milwaukee man sustained non-fatal injuries. The victim arrived at a local hospital for treatment. The circumstances leading up to the shooting are under investigation. 

Milwaukee police are investigating a third shooting that happened at approximately 11:05 p.m. near W. Windlake Ave. and Becher St.

A 19-year-old Milwaukee man also sustained non-fatal injuries. The victim was conveyed to a local hospital for treatment. The shooting was the result of an armed robbery. Milwaukee police continue to seek unknown suspects.

Anyone who may have information on any of these shootings or was a witness to an incident is asked to contact Milwaukee police at (414) 935-7360 or Crime Stoppers at (414) 224-TIPS or P3 Tips App to remain anonymous.