A 16-year-old boy remains in custody while police investigate a report of a sexual assault in Weymouth town centre.

The incident was reported to have occurred outside an address in Frederick Place at around 4.30am on Saturday. The victim is an 18-year-old local woman.

A full investigation was launched by detectives and Dorset Police said today, Sunday,  a 16-year-old boy from Poole had been arrested on suspicion of attempted rape. He is assisting officers with their enquiries.

Detectives are continuing to appeal for any witnesses, or anyone with information, who have not already spoken to police to contact them.

Yesterday police moved to try and reassure the community – following the shock attack on the 18-year-old woman in a doorway in the early hours of Saturday.

The offender was said to have fled the scene when a neighbour heard the woman's screams and ran to her aid.

Police said the victim, a local 18-year-old woman, had left Actors Club in Maiden Street at around 4.15am on Saturday, when she was approached by a man in St Mary Street, who walked with her until they got to Frederick Place.

The assault occurred in the entrance area to an address.

A neighbour heard the victim screaming and arrived at the scene, at which point the offender ran off.

On Saturday, police issued a description of the alleged offender - he is described as black, of athletic build and aged in his late teens to early 20s with short shaved black hair and facial hair.

He was wearing a dark-coloured top and light-coloured jeans as well as a black scarf. He told the victim that he was from Bournemouth.

Detective Sergeant Dave Horn, of Weymouth CID, said: “We have launched a full investigation into this incident and are continuing to support the victim.

“We are carrying out a number of enquiries, including a review of CCTV footage in the area, and a cordon has been put in place to allow for an examination of the scene.

“I am appealing for any witnesses or anyone with information about this incident to please contact us.”

Earlier, a policeman was standing guard at a doorway in the area.

Chief Inspector Steve Yeoman, of Dorset Police, said: “I would like to reassure the local community that a full investigation is underway to identify the man responsible for this offence.

“There will be an increased police presence in the area as this investigation continues and officers can be approached by residents with any concerns.”

Anyone with information is asked to contact Dorset Police at www.dorset.police.uk, via email 101@dorset.pnn.police.uk or by calling 101, quoting occurrence number 55190074677. Alternatively, contact Crimestoppers anonymously on 0800 555 111 or via www.crimestoppers-uk.org.