Do you recognise any of these people?
The 16-year-old was left with serious facial injuries after the assault on a 248 bus last month.
The boy had been sitting on the bus when the group called him over to them.
When the victim went to join them, he was attacked by two of the suspects.
Investigators from the Metropolitan Police’s Roads and Transport Policing Command have released pictures of four males they would like to identify.
Detective Constable Amanda Hawke said: “This is a cowardly and shocking act of violence which left a teenager in a serious condition.
“I am keen to speak to the two male passengers sitting at the rear of the bus at the time of the assault and for the suspects or anyone who knows them to come forward.”
The incident happened at around 2.55pm on Monday, 2 November.
Police were called to the bus and the victim was taken to hospital.
Anyone with information is asked to call police on 101 quoting reference Cad 4587/2NOV20. Alternatively, Tweet @MetCC or contact Crimestoppers anonymously on 0800 555 111.
For more on this story, and the latest on our other local and national news, listen to Time 107.5FMTags: Havering, Upminster, Bus, Public Transport
© TIME107.5fm 2015-2021. All rights reserved.