BBCWarning: Contains desciptions of sexual abuse
Vulnerable women and girls as young as 14 are being lured into a world of forced sex by gangs in London, evidence uncovered by the BBC has found.
Some told us they had been raped by several men as "payment" for unpaid drug debts run up by the gangs that controlled them, while others said they had been groomed just for sex.
Our evidence - based on interviews with dozens of people in the capital over several weeks, including five survivors of gang-based violence - also shows how girls are often lured by groups of men into dealing drugs, trading weapons and stealing phones.
One police officer in London said young girls and women were the "lowest rung" in gangs and were groomed and exploited "for everything".
Public attention on grooming gangs has often centred on the north of England. A government-commissioned report last year found in three regions - Greater Manchester, South Yorkshire and West Yorkshire - there was enough evidence to show "disproportionate numbers of men from Asian ethnic backgrounds amongst suspects for group-based child sexual exploitation".
Our investigation reveals a complex picture in London, with gangs from a range of ethnic backgrounds, including white, operating widely in the capital and frequently exploiting young women.
Last year, Mayor of London Sir Sadiq Khan said there was no "indication of […] grooming gangs" - of the type seen in Rotherham and other towns - operating in the capital.
However, a spokesperson for Sir Sadiq recently told the BBC he wanted to support police to do everything possible to tackle "all child sexual exploitation in the capital, including grooming gangs".
Kelly, not her real name, said she had been groomed by three white men in the capital. She was initially forced to deal drugs but said the exploitation then got worse.
"I had no money, felt neglected and saw an opportunity to feel part of something so I made some bad connections and before long I was selling drugs on the streets. But that turned into having sex to keep people on side if we owed them, or [as an enticement for them to] buy drugs off me and the gang," she said.
"I didn't feel like I was groomed or exploited. I didn't think I was a victim. It's taken me a while to realise I was used and manipulated.
"It gave my life purpose for a bit and I felt needed," she added. "I didn't feel that at home. I was looking for something because I [was] lonely and bored."
Girls inside gangs "cannot say no to sex", said Det Sgt John Knox, head of the Metropolitan Police child exploitation team in the south London boroughs of Lambeth and Southwark.
"Within that gang world, the girls are at the lowest rung and they have to do as they're told. And that includes sexually."
Girls were not exploited, he said, "predominately and primarily for sex" by gangs. He added: "The girls are groomed and exploited for everything - within that is sex."
Knox believes there are at least 60 children in his area of south London who are being exploited by gangs.
He said the girls are as young as 13 but "15 would be the upper limit".
"The reality is, if a girl can't say no, she's being raped and that's how we look at it as the police."
A mayor of London spokesperson said: "Any individuals, groups or grooming gangs exploiting children for sex are utterly abhorrent and [Sadiq Khan] wants justice for every single victim of these horrific crimes.
"The mayor is clear that the Met must follow the evidence wherever it leads and he will continue to ensure it does everything possible to tackle all child sexual exploitation in the capital, including grooming gangs, to build a safer London for everyone."
Met deputy assistant commissioner Kevin Southworth said the grooming gang issue was "very high" on the force's "threat and risk radar", and it was committed to putting as much of its resource into combatting the problem as much as possible.
"We are very, very acutely aware of the risk of grooming gangs here in London and their prevalence," he added.
"We have seen examples of grooming gangs whether they're grooming children for criminal exploitation or sexual exploitation."

Social workers caring for victims explained to us how many of those exploited were vulnerable because they had come from broken homes or had had other troubled backgrounds like abuse, drugs or poverty.
Milly, not her real name, told the BBC her experience of grooming gangs in London did not involve selling drugs and mirrored what had happened in towns and cities such as Rotherham, Rochdale and Oldham.
"I was 15. I was getting passed around different men every night - sometimes 10 or 15 a month," she said.
"They just give us drink, give us drugs. Next thing I know, I'd just be in the bedroom with one of them. Then I'd come out. Could be another one. After that it could be another one. Sometimes it was only one. Sometimes it could be three. And then we'd just leave really."
She said, even though it had happened a few years ago, she couldn't recall many of the details because she had been so intoxicated at the time.
"I don't remember their names really. It sounds horrible, but I just know they were [South] Asian.
Sometimes they just said, 'Oh, you're a nice, young white girl'."
Another London survivor, whom we are calling Ruth, said she was also exploited for sex.
"They didn't want anything but sex. I was low and they gave me expensive things so I felt wanted and then slept with them. It felt like I had multiple boyfriends giving me attention. They were South Asian men - they took advantage of my situation.
"It's happening in London," she added. "And those who don't believe it need to look again."
The women we spoke to say their stories prove that not all grooming-gang cases in the city involve drug dealing and other criminality.
However, one solicitor warned against racial generalisations of perpetrators. Alan Collins, from Bolt Burdon Kemp, who specialises in child abuse cases, said he represents several survivors who have been groomed, including women in London.
"I think one needs to be very careful in drawing any conclusions because of the abject failure to record nationally the ethnic background of the men who are convicted of abusing these children and young people," he said.
Police officers, social workers and some of the survivors we have spoken to insist gangs operating in London come from much wider ethnic backgrounds.
"From the reporting that we have, we do not see a disproportionate number of any one particular ethnicity or nationality within our suspects, which straddle the entire diverse range of London's communities, as you would expect in a multinational city like London," said Southworth, the Met's deputy assistant commissioner.
One London victim we spoke to, said her experience involved men of "different races, ages and religions".
About 2,000 child exploitation cases are reported to the Met every year. These relate to child sexual exploitation, child criminal exploitation, or cases where both forms of harm were present.
The Met has already announced it will be re-examining at least 1,200 cases of child sexual exploitation, following a national review into group-based child sexual exploitation.
A report by Baroness Casey, published last summer, also found a mismatch in the way the Met recorded child abuse.
The force said there had been significant improvements in how it identifies and investigates group-based offending, including training for 23,000 front-line officers and the expansion of its child exploitation teams.
An independent inquiry into grooming gangs chaired by Baroness Longfield CBE is expected to begin later in the year.
A Home Office spokesperson said the inquiry would have "full powers to compel evidence and hold local investigations".
They said child sexual exploitation cases that had previously been closed were now being reviewed "so the evil perpetrators who committed these crimes - and thought they got away with it - will have nowhere to hide".
A list of organisations in the UK offering support and information with some of the issues in this story is available at BBC Action Line.
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