PC Nathan Lucy swam out after the woman, who'd jumped into the water from the Red Jet terminal.
Police Hunt Southsea Sex Attacker
Police are putting out an e-fit picture of a man they want to find as part of a renewed appeal after a sexual assault was reported in the early hours of the morning on Saturday, September 8, 2012.
A 24-year-old woman was on Southsea Common when she was approached by a man she didn't know near the junctions of Western Parade, Kent Road, Southsea Terrace and Castle Road at around 3.30am.
It's alleged the man sexually assaulted her before a second man came to help her and stopped the attack.
The woman then made her way to Elm Grove where she spoke to other members of the public and the police were called.
The woman received minor injuries, which did not require any treatment. She is now recovering at home.
Detective Constable Nick Wieczorek said: "The woman was described as being in a distressed state and police are keen to speak to anybody who had contact with her that evening, particularly a man who came to her assistance on Southsea Common. He may have vital information about the assault. "It is known that the woman spoke with a number of people in Elm Grove before police were called and it is important we identify as many of these people as possible. Any of them could also have information, which is vital to the investigation. "This investigation is not linked with any other sexual assaults or reports of crime."
The man described in the e-fit as the woman's suspected attacker was: * 24-27 years * 5ft 4-5ins * Slim build but with muscle * Short dark hair, which was longer on top and flicked up at the front * A gash of a scar on the right side of his face. * He was clean shaven.
Witnesses or anyone with information are asked to contact CID at Cosham police station by phoning 101. Mini-Com users can call the police on 18001 101.. Information can be given anonymously by calling the Crimestoppers charity on 0800 555 111.
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A section of Parkstone Road will be affected between 9.30am and 4.30pm for three days.
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