Justin Bieber may be in trouble with the law again.
The Los Angeles County Sheriff's department confirmed to ET on Thursday that the 22-year-old singer is being investigated for an incident at a Los Angeles restaurant.
"There is an open investigation where someone inside the establishment called and said that something happened with him [Bieber] outside," the sheriff's department tells ET.
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However, what actually happened is still being determined, authorities say, and they have yet to speak to Bieber. Police also tell ET that they haven’t confirmed that Bieber was involved in the battery case.
Reps for Bieber did not respond to request for comment.
Bieber allegedly headbutted a man at a pre-GRAMMY party last weekend at Serafina restaurant, according to TMZ, and cops are now investigating the incident as a possible crime. Bieber was reportedly "play fighting" with former That's So Raven actor Kyle Massey at 2 a.m. Saturday, when he allegedly got upset at somebody recording him and refusing to delete the video. The "Baby" singer then allegedly headbutted the man -- prompting a person at the scene to call the police -- though Bieber left before deputies arrived.
A representative for Serafina restaurant told ET on Thursday that nobody from their staff was involved in the incident.
"We know very little about the alleged incident at Serafina Sunset with Justin Bieber, but we can assure you that nobody from our staff was involved, nor did we call the police," Caroline McBride, Director of Public Relations for Serafina Restaurant Group, tells ET. "We always have pleasant experiences with Mr. Bieber whenever he comes to Serafina."
According to TMZ, the alleged victim doesn't want to press charges against Bieber, but the misdemeanor battery investigation is still ongoing.
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Bieber didn't attend the GRAMMYs on Sunday, but on Tuesday, he did take to Instagram Stories to share that he didn't "have a Valentine."