Image copyright Getty Images Image caption Official estimates of the number of girls abused in Rotherham are conservative, according to support workers

Asian - as well as white - girls are being groomed for sex by Asian men in Rotherham, victim support groups say.

Support workers believe that a report on children abused in the town between 1997 and 2013 may have under-estimated the number because it was unlikely to include the experiences of Asian girls.

The Jay report, published in August, put the figure at at least 1,400.

But Yasmin Ishaq, who has supported victims, said: "It's not just the young white girls that they're targeting."

Ms Ishaq, who runs a voluntary organisation, said men who they knew to be abusers had never been prosecuted and were also systematically abusing young girls within their own network of family and friends.

She told BBC File on 4: "The Pakistani girls are not going to be part and parcel of this report. There's no record of what's happened to them. They're too afraid to have ever gone to the law.

"The men will get away with this because nobody wants to address it and nobody wants to own up to the fact that their daughter has been molested."

Although none of the victims would talk directly to the BBC, File on 4 heard reports of some Asian girls being blackmailed by grooming rings, while others were forced at knifepoint to perform sexual acts on men.

Image caption Ms Ishaq said one young woman told her she was systematically raped by five men

Ms Ishaq described how one teenage girl she had been helping was taken to what she thought was a party by her boyfriend.

"When she got there, there was no party, there were no other female members present. What she found was that there were five adults, their ages ranging between their mid 20s going on to the late 40s and five men systematically, routinely, raped her. And the young man who was supposed to be her boyfriend, stood back and watched."

Ms Ishaq explained that the group photographed the abuse and threatened to publish it unless she did as she was told.

Genuine fear

"This is what is being said to her now: that if you do not comply, we will be submitting these photographs not only to your parents, to your fathers, to your brothers, but we will actually be posting them to local mosques," she said.

"She is still currently in this hell-hole. She cannot see how by going to the police or asking for their help, she can save herself from the consequences of what her family will do to her. She has a genuine fear that she will be beaten, she will be taken abroad, she will be forced into a marriage she doesn't want to be in."

Find out more Listen to File on 4: The Last Taboo on 28 October at 20.00 GMT or later on iPlayer.

Other organisations told the BBC they had heard similar stories of abuse in the town.

"There's a particular woman with learning difficulties that we're supporting and she will show you pictures on her phone of about six to eight different Pakistani men. She's adamant they're all her boyfriends," said Zlakha Ahmed, head of Apna Haq, a group that supports women from ethnic minorities in Rotherham.

"She talks about the chocolates, the phones, the clothes, the presents, that they buy for her. They regularly pay for her train fare so she can go down to Manchester, Blackburn, London, Birmingham.

"When she arrives she'll go to a really posh hotel, she meets a number of these men and she's introduced to some of their friends. Then she'll always say, 'I was given a drink and I don't remember what happened then'.

"She talks about how she wakes up in the morning and her legs hurt badly, and she's had a number of abortions. For us, that is gang-related abuse of a vulnerable woman. We know this is one young woman. How many others will they be abusing?"

There are no official figures for the number of cases of sexual abuse and grooming within the Asian community, and the Crown Prosecution Service does not record the ethnicities of the women in the cases that come to them.

But because of the culture of honour and shame protecting these cases, only a very small proportion are even reported to the authorities.

Listen to File on 4 on BBC Radio 4 on 28 October at 20.00 BST or later on iPlayer.