Ten people were taken into custody in the downtown shooting and nine firearms were recovered, according to the police capt. Warren Allen of Milwaukee.
The 17 people who were shot ranged in age from 15 to 47, Allen said.
All victims of both shootings are expected to survive, he said.
Multiple shots and screams can be heard in a video taken by someone at the downtown shooting scene.
“We were waiting for a Lyft, walked through that intersection three minutes earlier and knew something wasn’t right, so we ordered it to pick us up,” the person who made the video told CNN.
“People in the middle of the street were just loud and obnoxious,” he added. “People are yelling back and forth at each other.”
The shooting near the arena left two men, 26 and 29, and a 16-year-old girl injured, according to Allen.
“A 19-year-old man has been taken into custody in connection with this incident,” Allen said. “The charges are pending review by the Milwaukee County District Attorney’s Office.”
That incident occurred around 9:12 PM near the intersection of Martin Luther King, Jr. Drive and Highland Avenue, about a block from the Bucks Court on Fiserv Forum.
Police have not released the names of those involved or a possible motive.
The Bucks lost to the Boston Celtics on Friday night — 108-95 — forcing a seventh game on Sunday to determine who will play the Miami Heat in the Eastern Conference Finals.
Lechelle Benken and Sara Smart of CNN contributed to this report.