As many as three people were taken to the hospital, but no fatalities have been reported, according to initial reports.
The shooting took place near Minooka Park at Racine and Guthrie Road in Waukesha, located in Waukesha County. Officials say the suspect had a court order of protection against him.
Waukesha is 18 miles west of Milwaukee. Just 10 miles away in Brookfield on Sunday, a man opened fire in a spa, killing three and wounding four.