A second teenager has been arrested after a 15 year-old boy was assaulted at Barry Island.
A 17 year-old boy from the Ely area of Cardiff is being questioned in connection with the incident near the Paget Road car park at around 7.30pm on Tuesday 12th August.
The victim, who was allegedly attacked by a group of males, needed hospital treatment for minor injuries.
A 16 year-old boy from the Gwent area has also been arrested and bailed.
South Wales Police described it as a a "cowardly and vicious attack...which could have ended far worse".
On Friday, Detective Inspector Philip Marchant from Barry CID said: "Our investigation into the incident is continuing and anyone who may be able to assist is urged to get in touch."
"Local officers are continuing to patrol the area during these busy Summer months to ensure the public are able to enjoy what the area has to offer feeling safe and reassured."
Footage from social media has also been examined as part of the investigation.
Detectives are still appealing for witnesses or anyone with information to contact South Wales Police on 101, or use the live web chat, quoting reference no. 2500258409.

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