A man was left with a broken jaw and fractured skull after being assaulted in Hull.
Humberside Police today released details of the attack, which took place in George Street on December 2.
The victim was taken to hospital for treatment after he was knocked unconscious during the altercation.
A spokesman said: "We now want to trace four men and a woman in connection with this incident which occurred around 5.30am.
"The suspects may be from out of the region and possibly from the south of England.
"CCTV images taken on the night of the suspects are not high definition, but we are asking for anyone who may know the suspects or may have any information to contact us."
Please call 101 quoting log 112 of 2/12/17.