A Portland teenager has been arrested over the attack on a student who was walking two girls home from a party in the quarries.
An 18-year-old Portland man was arrested and has been released on bail while inquiries continue.
Stuart Purnell, 17, sustained a possible broken jaw near to the Naval Cemetery at around 11.30pm on Friday, July 16, and was taken to Dorset County Hospital.
Police had found out about the party but said on arrival the people had dispersed.
Detective Constable Ed Meanwell, of Weymouth CID, said: “There was a well-publicised party taking place near the Naval Cemetery last Friday and there were many people in and around this area at the time of this incident.
“The victim was allegedly struck to the face and I understand that this caused him to fall to the ground.
“I believe that a group of girls were standing near the victim at the time of this incident and that one of these girls may have spoken with the victim shortly after he sustained his injuries – it may be that these girls can help me find out exactly what happened.
He added: “Any information, no matter how small or insignificant you believe it to be, could help me with this investigation.”
DC Meanwell wants anybody who witnessed the assault or who has any information to contact him urgently on 01305 222222.
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