A gang attacked teenagers on the Downs during a night of crime where one victim's nose was broken.
The youngsters were kicked, punched and hit with sticks during separate robberies.
Speakers, bank cards, cash and a bike were all stolen during the incidents.
Officers have stepped up patrols in the area following the assaults at 8pm, Friday (July 10).
The victims, who were all aged between 15 and 18 years old, were separately approached by a large group of teenagers.
The attackers were described as black or mixed race and all aged in their early to mid-teens.
DI Clem Goodwin said: “This was a linked series of robberies in which young people on The Downs were approached, threatened and had their property taken.
“Some of the victims were assaulted by being punched, kicked or struck with a wooden stick, while in one of the incident a teenage boy who tried to intervene was assaulted and suffered a broken nose.
“Officers attended The Downs and took some of the victims in cars to search the area but the offenders could not be picked out or located.
“We’re now carrying out further enquiries and will be taking statements from all the victims and reviewing CCTV from around the area.
“Extra patrols will take place over the weekend to deter further offences and provide reassurance.
“If anyone has information on those involved, or has been a victim of an offence and not yet disclosed it to the police, please get in touch.”
If you can help, please call us on 101 and give the call handler the reference number 5220152774.
