A boy of 12 was taken to hospital after being attacked and left unconscious in Brighton on Sunday (23 January).
Sussex Police issued an appeal for witnesses or anyone with information about the assault in Hodshrove Lane, Moulsecoomb.
The force said: “Police are appealing for witnesses after a 12-year-old boy in Brighton was assaulted by a group of young people on Sunday morning.
“The victim reported being approached by a group of around six teenagers at a basketball court in Hodshrove Lane between 10.30am and 10.45am.
“He was then assaulted and left unconscious, before being helped by two women passing by. He attended hospital to have his injuries assessed.
“The group are described as having hoods up and wearing masks and bandanas.
“Officers would like to speak to anybody who witnessed the incident or has any information that could help with the investigation, particularly the two women who stopped to help.
“Contact police via the Sussex Police website or by calling 101, quoting serial 442 of 23/01.”