Detectives investigating an alleged assault on a teenager are renewing their appeal for witnesses and information.

And officers are urging local parents to be vigilant following reports that a small number of young men may be planning further trouble.

At approximately 1.15am on New Year’s Day officers received a report of a fight near to the Shore Road shelter, close to the beach front. When officers arrived at the scene they found that three teenage boys had suffered injuries – one of these boys suffered a serious head injury.

He was taken to Poole Hospital and was later transferred to the neurological unit at Southampton Hospital.

A 17-year-old boy from Lytchett Matravers has been arrested and bailed while police make further enquiries.

Detective Inspector Stewart said: "From our enquiries, we know there were a large number of young people on the seafront by the blue shelter on Shore Road at the time of this serious incident.

“We are directly appealing to these young people to speak to police if they witnessed this incident which has left three teenagers with injuries.

“Equally, if anyone has heard any information while at school or college – or on social networking sites – about those responsible, I’d urge them to inform police and this will be investigated.”

The 16-year-old boy, from Swanage, remains in hospital in Southampton where his condition is described as serious but stable.

Anyone who witnessed this incident, or anyone who has any information should contact Dorset Police on 101 quoting incident 1:202 or Crime stoppers, in confidence, on 0800 555 111.