LAPEER, Mich. (AP) — Police have lifted a voluntary evacuation of downtown Lapeer, Michigan, after gasoline from an unknown source apparently leaked into the city’s sewer lines.

Lapeer Police Chief Dave Frisch says the evacuation was lifted Wednesday afternoon after being in place most of the day. Partial road closures remained in place.

The evacuation ended after officials said every sewer manhole in the affected area was tested for levels of gasoline vapors and workers sought to contain the suspected source of the leak. The source was not immediately identified.

Police discovered the leak early Wednesday following reports that sewer explosions may have dislodged several manhole covers in the city about 45 miles northwest of Detroit. Barricades were set up to block access to downtown.