Police in Brighton are searching for a man who sexually assaulted a young woman on her way home.
They also believe the same man could be responsible for a similar assault in the city in July.
The 19-year-old victim was walking east along the north pavement in Marine Parade, Brighton, at about 5.30am on Sunday (6 October) when she was approached by the man who first tried to engage her in conversation and then attacked her at the junction of Seymour Street.
She resisted and after some moments she managed to struggle free and ran off.
The man is described as of mixed race, tall and in his late thirties, with flat black afro-style hair and wearing square-rimmed glasses.
Detective Inspector Duncan Elliott of the Brighton Safeguarding investigations Unit said: "This was a very frightening experience for the woman, who is receiving support and assistance from specialist officers.
"It is vital that we trace this man and an intensive investigation began immediately on Sunday morning. If you were in the area early on Sunday morning and saw anything of this incident, even without perhaps realising what was happening at the time, or if you saw any other suspicious activity or can help us identify this man, please contact us online (link will be added) or by calling 101, quoting serial 293 of 06/10."
Detectives are also considering the possibility that the same man may be responsible for a sexual assault on a 22-year-old woman who was walking home in Ditchling Road, Brighton, at about 1.35am on Wednesday 24 July, when she was approached by a man of similar description at the junction with Princes Crescent, who again tried to engage her in conversation. He then sexually assaulted her but she resisted and he made off back down towards London Road and disappeared.
Duncan Elliott added; "We have carried out very thorough and detailed enquiries into this attack including visits to all addresses in the vicinity, and the victim has also been receiving support from specialist officers, but so far the assailant has not been traced. Again if you have any information that could help our investigation into that attack, please contact us online or by calling 101, quoting serial 208 of 24/07.
"From the descriptions in each case, and the circumstances of the attacks, including other information, we believe they may well be linked.
"However they are isolated incidents and not part of any wider pattern. Our investigations are continuing and our patrolling officers are paying extra attention to the areas involved and anyone with concerns can speak to them at any time."
For information and advice on staying safe when out and about see the Sussex Police website