CHICAGO -- The Chicago Cubs have filed a lawsuit against several people whom the team accuses of being behind a fake mascot that has been engaging in bad behavior near Wrigley Field, including getting into a bar fight that was captured on video and posted online.

The Cubs have filed a lawsuit against five people whom the team says dress in the "Billy Cub" bear costume. Jerry Lai/USA TODAY Sports

The team filed its lawsuit on Friday in federal court in Chicago against John Paul Weier, Patrick Weier and three other unnamed individuals whom the team says dress in the bear costume, the Chicago Sun-Times reported.

The fake mascot -- not to be confused with the team's new official mascot, "Clark the Cub" -- wears a Cubs hat and No. 78 jersey that has the name "Billy Cub" on the back. The team says the defendants are trying to pass their character off as an official representative of the team, and it accuses them of trademark infringement, injuring the team's reputation and unfair competition.

The team accuses those behind the fake mascot of demanding tips for photos, making "rude, profane and derogatory remarks and gesticulations," and punching a man at a bar near the ballpark. The punch, which was caught on video, was posted on YouTube and was widely viewed. The Cubs say fans were confused and thought the official team mascot had thrown the punch instead.

The lawsuit wants the defendants to stop using the character and requests "deliver for destruction" the costume's components. It also is seeking payment for damages and legal fees.

The nature of the Weiers' relationship wasn't immediately clear, and neither of them could be reached for comment.