The 25-year-old man, who was convicted of second-degree sexual assault of a child, was arrested for violating terms of his probation that forbade contact with children, the Milwaukee Journal-Sentinel reported Friday.

Officer Michael Gasser said he approached the truck, which was being driven by the man's girlfriend, because it was blocking traffic at about 8 p.m. Thursday while people were gathering to watch a fireworks display on the east side of the city.

Gasser said he saw the man in the truck while he was instructing the driver to move and asked to see his identification. District 5 Sgt. Janice Shoman said the man was arrested after Gasser ran his information.