Havering Police: Do you know these men?
Police want to talk to these men after a youth was attacked in Romford town centre.
A 19-year-old, from Waltham Forest, north-east London, was socialising when he was set upon by a gang of four men, at around 3am on Sunday February 20.
The suspects may be have links to Ilford, Chingford and Newham, in east London, a police spokesman said.
The victim needed more than 30 stitches after receiving serious cuts to his head, eye and neck.
Witnesses or anyone with information should call DC Paul Swift at Romford Police Station on: 0300 123 1212.