GREEN BAY, WI -- Residents in Green Bay have been wary of a mysterious clown spotted roaming the streets of the city at night this week.

The clown, dubbed 'Gags' by local residents, was first spotted at 2 a.m. Monday according to a Facebook page that has been created to track sightings. It's not clear as to how or why the clown got its name.

Photos of Gags showing up on social media show the clown, dressed in a tattered dark gray suit with what appears to be a bald white head and holding black balloons.

According to Chicago TV station WMAQ, some Facebook commenters claim the clown is part of a recent shooting of a scary movie.

Some neighbors, unnerved by the sight of the creepy clown, have called local police. And while police say they have received a number of calls from residents concerned about the clown, legally, there is not much they can do.

"A person can walk down the sidewalk dressed however they want," Green Bay Police Capt. Kevin Wary told Green Bay TV station WGBA. "As long as they're in a place where they legally can be and they're not in a place that has a closing time, like a park, they can be there, and dressed however they want."

Police say they have limited options in dealing with the situation.

The photos of Gags have gone viral, and according to WGBA, as of midnight Tuesday, the original photo had been shared more than 8,000 times.