Extra police are patrolling Glasgow city centre after a 38-year-old woman was raped by three men in the early hours of Friday morning.
Police said the victim became aware the men were behind her when she was making her way home on Renfield Street at about 0015 GMT.
She was attacked in Renfrew Lane, next to the Pavilion Theatre.
The suspects are described as of Middle Eastern appearance, in their early 20s, of average height and slim build.
One wore skinny jeans and a light-coloured brown jacket or top.
Police are examining CCTV from the area in an effort to identify the men.
Supt Val Thomson, of Strathclyde Police, said: "This was a terrifying and extremely distressing attack on the woman who had been on a night out with her friends in the city.
"They had left each other to head home and she was on her own when the attack took place.
"I would appeal to anyone who was in the Renfield Street area around the time of the incident or who may have seen the suspects in the area or even witnessed the attack to come forward."
Supt Thomson advised women not to go off on their own during a night out.