WASHINGTON, Aug 1: A man armed with an assault rifle walked out of the woods in Wisconsin and fired into a group of young people gathered at a river to go swimming, killing three teens and wounding a 20-year-old, local media reported on Friday.

Authorities had a suspect in custody after launching a massive manhunt along the Wisconsin-Michigan state line for a man between 30 and 50 years old wearing camouflage clothing, local television station WBAY reported online.

The victims were shot on Thursday afternoon while they gathered with a group of a nine young adults near a railroad bridge located on the Menominee River, which forms the Wisconsin-Michigan state border and is near the city of Niagara, local media said.

The victims were 17, 18 and 19 years old. A 20-year-old man who suffered minor injuries.—AFP