Police investigating the rape of a woman in Glasgow want to trace a key witness who helped the victim after the attack.
The 30-year-old woman was assaulted on the Broomielaw, near the railway bridge over the Clyde, late on Monday evening.
Police want to speak with two men who were spotted on CCTV in the area.
One of them helped the woman to a nearby casino while the other was nearby and may have witnessed the attack.
Det Insp David MacGregor said: "This was a traumatic attack for this woman and it is critical that we trace the person responsible as soon as possible.
"Our officers are doing everything they can, including an extensive review of CCTV in the area, however, we need help from members of the public who may have vital information to assist with the investigation and therefore we are appealing for these two men to come forward.
"The first man is seen helping the 30-year-old woman shortly after the attack and had walked her to the Riverboat Casino. The second man is seen nearby, and may have witnessed the attack or have information that can help us."
The first man is described as white, aged between 25 and 35, around 5ft 8ins tall and of medium build, with brown hair in a side parting.
He wore a dark zip-up jacket and was carrying a black rucksack.
The second man is described as having sallow skin, is of medium build and was wearing a light-coloured zip-up hooded top with a white logo and a dark skip cap.
Anyone with information is asked to contact police via 101, quoting incident number 4697 of 16 July.