A teenager with Down's Syndrome has told a court how she was raped by one of three men accused of sexually abusing vulnerable girls.

The "trusting" young woman, said not to have the capacity to consent to sex, alleged she was led into a bedroom and undressed by Nasir Huq in April 2013 when she was 17-years-old.

Mr Huq, 18, is on trial alongside friends Ameen Noori and Ahmed Faiq, both 18, who are each accused of raping a 16-year-old girl with learning difficulties in Mr Huq's flat in Frith Road, Croydon.

Prosecutor Jonathan Polnay told Croydon Crown Court the three men "outrageously took advantage of vulnerable girls with learning difficulties to satisfy their own sexual urges".

Giving evidence by video-link yesterday, the eldest alleged victim, judged to have an IQ of 57 by a consultant forensic psychologist, told a jury Mr Huq had anally raped her when she stayed overnight at his flat with three friends.

The teenager, now 19, said: "I didn't want him to take my jeans off. He laid down on me. He had to force it into me."

She said the attack stopped when her friend walked in and Mr Huq left "embarrassed". 

The jury also watched a video of a police interview on April 26, eight days after the alleged attack, in which the victim told an officer: "He turned me around. His 'down below' went in my bottom by an inch. I said 'oh god stop'."

Mr Huq, now of Neville Road, Selhurst, claims the teenager consented to sex. But the psychologist who assessed her concluded her "significant confusion about sexual matters", including a lack of understanding of pregnancy and sexually transmitted diseases, meant she did not have the capacity to consent.

Mr Polnay said: "The prosecution say that [the alleged victim] is simply not able to truly and freely consent to sex, as due to consequences of Down's Syndrome she simply wouldn't be able to process what was proposed or its implications."

Mr Noori, of St James's Road, Croydon, and Mr Faiq, of Parry Road, South Norwood, are accused of raping the younger girl who is described as having a "borderline range of intellectual functioning".

The court heard she struggled to get free and shouted, "just leave me alone, I want to stop, I just want to go" as Mr Noori attacked her on April 5. 

Mr Polnay said: "But Ameen did not listen. 

"The Crown's case is quite clear: [the victim] did not consent with Ameen. Given the circumstances, Ameen couldn't have reasonably believed she consented either. He simply didn't care."

After leaving the room, the girl was then allegedly raped by Mr Faiq. The jury heard she was "too scared to say anything" but tried to stop him, making it clear she did not want to have sex. 

She was again raped by Mr Noori when the girls returned to the house on April 18, the court heard. 

The three men were arrested after the elder victim told her mother she had been raped, having been found crying at the roadside outside Mr Huq's flat.

Mr Faiq is charged with rape and attempted rape, Mr Noori is charged with two counts of attempted rape and one of rape, and Mr Huq is charged with rape. 

All three deny the charges.

The trial continues.