The alleged assault took place on September 14 and left a man in his 20s requiring hospital treatment. A spokesman for Cambridgeshire police said: "The victim was at the Olmo Lounge with friends on Saturday, September 14, when, at about 10.30pm, he was hit from behind and knocked to the floor. "He suffered minor injuries as a result and was taken to Hinchingbrooke Hospital." Anyone who recognises the man pictured, or has any information, should call police on 101 quoting 35\/65918\/19 or visit www.cambs.police.uk\/report. Alternatively, contact Crimestoppers, anonymously, on 0800 555111 or via www.crimestoppers-uk.org.