Three young people were killed and another one was wounded on Thursday afternoon when a man dressed in camouflage and armed with an assault rifle emerged from Wisconsin woods and opened fire on a group of young swimmers gathered near a river.

After a whole night of manhunt, Scott J. Johnson, aged 38, came out of the woods close to the shooting scene and dropped his weapon as officers advanced toward him, according to Jerry Sauve, chief’s sheriff’s deputy in Marinette County, cited by the Associated Press.

Nine young individuals had met at a railroad bridge in order to go swimming in the Menominee River when the gunman showed up and opened fire, authorities reported.

Officials declared they were not aware of any motive for the attack or any connection between the suspect and the victims, whom they identified as Bryan Mort, 19, Tiffany Pohlson, 17, and Anthony D. Spigarelli, 18. Daniel Louis Gordon, 20, the person who was injured in the assault, suffered minor injuries, officials said.

The Associated Press reported that a judge in Michigan’s Dickinson County requested Johnson on Friday to keep distance from a 24-year-old Kingsford, Mich. woman. She says that Scott Johnson sexually assaulted her on Wednesday in the same region where the shooting took place and then went into the woods of Wisconsin. The order forbids the attacker from following the woman, showing up at her home or work place, or even threatening her.

The woman told the Associated Press on Friday night that she had reported the incident to police on Wednesday night. Furthermore, she said officers came to her home late Thursday, pointed out the shootings and asked her to describe her aggressor.

According to the same source, authorities did not return calls asking for comment on whether charges were being prepared in the physical attack.