Police are looking for a man who assaulted a 22-year-old woman from behind with a bottle at Brooklyn club Union Pool. The unprovoked attack happened around 2:50 AM on February 23 and The NY Daily News reports that the man came up behind the woman, cracked a bottle over her head and ran off. The victim was hospitalized for a concussion, pain and bruising. Police say there had been an argument in the bar earlier but it is unclear of the two incidents are related.

The attacker has not been caught and NYPD asked for help locating him today, releasing surveillance video of the suspect. If you have any information, please call NYPD Crime Stoppers at (800) 577-TIPS. Surveillance video of the suspect, via Crime Stoppers, is below.