Detectives in Preston have released a computer-generated image of a man they are hunting over a serious sexual assault.
The 37-year-old victim was in Moor Park when she was grabbed by three men, held down by two of them and sexually assaulted by the third.
She eventually managed to escape and run away after the attack, described by police as "horrendous".
The main attacker is described as black with a muscular build and shaved head.
One of the other two men is described as white, in his early 20s with dirty ginger hair tied in a pony tail.
Det Insp Dave McKenna said: "This was a horrendous attack on a lone woman which has left her utterly distraught.
"I would urge anyone who thinks they recognise the man in the evofit [image] or the descriptions of the offenders given by the victim to contact police."
The attack happened on the evening of 24 June and police are urging anyone who was in the park to come forward.
"Any amount of information, no matter how small, could be crucial to this investigation," added the detective.