12 held over 'child sex ring'
Detectives believe they have smashed a child trafficking gang preying on runaways as young as 11 for Britain's sex trade.
Twelve men are being questioned in Oxford by police investigating claims 24 vulnerable girls under 16 were groomed for rape.
Officers suspect gang members targeted children in care or living rough and transported them around Britain over a six-year period.
Amid fears more children may be involved, patrols of officers took to the streets of the university city to hand out public awareness leaflets.
The men - aged between 21 and 37 - are being quizzed over a string of offences including causing the prostitution of females under the age of 18, administrating drugs for the purpose of rape, trafficking, grooming and rape.
Thames Valley Police became aware of the allegations after a number of girls were reported missing.
Detective Superintendent Rob Mason said: "We believe we have uncovered an organised crime group who have been running a business of selling young girls for sex.
"We have also identified a number of customers who we have reason to believe have used this service."
More than 100 officers took part in raids as the force executed 14 warrants across the city as part of an operation named Bullfinch.
Police were not willing to comment on the nationalities of any of the suspects but sources said many of the offences centred in or around the Oxford area.
Many of the alleged victims were said to have been "known" to children's services.
Mr Mason, speaking later at the force's city headquarters, said the inquiry was still at an early stage.
"We consider the girls to be very, very vulnerable and that's why they have been targeted," Mr Mason said.
"The girls have gone missing and when they returned they have made certain disclosures.
"Through children's services and Oxfordshire County Council we have become aware of some of the activities the girls have been getting into when they've gone missing."
Police suspect those arrested include both those behind the running of the network and the men that have paid for sex.
The officer added: "The investigation has been very challenging. The girls are very vulnerable and a number of them do not consider themselves to be victims."
Detectives are keeping an "open mind" as to whether there would be further arrests.
"It is going to be a long investigation," Mr Mason added. "Our priority is the welfare of the girls."
Much of the police activity today was centred near St Aldates police station in central Oxford. More than 40 uniformed officers and community support officers were handing out A5 flyers about the operation.
Police chiefs also posted a video on YouTube to reassure community members and urge any potential victims to come forward.
Officers are working closely with children's services, the Child Exploitation and Online Protection Centre and other forces that have been through similar investigations.
Police are also urging anyone who thinks they may have been a victim to contact ChildLine.
Superintendent Chris Sharp, the force's Oxford commander, said: "I understand today's events will have an impact on residents.
"My neighbourhood policing teams will be carrying out reassurance patrols in the area issuing information about the operation with contact details if people need further information, or would like to report any activity in relation to this investigation.
"There are individuals and groups who may seek to take advantage of the young and vulnerable and it is our job, working with our partners, to prevent whatever form of abuse takes place and bring those responsible to justice."
Oxfordshire county councillor Louise Chapman, cabinet member for children, young people and families, said the council's focus was now on care for alleged victims.
Peter Davies, chief executive at the Child Exploitation and Online Protection Centre, commended the police action.
"Tackling this devastating form of child abuse is challenging for police forces and other agencies, so I'd like to congratulate Thames Valley Police on these arrests," he said.
Sheila Taylor, director of the National Working Group for Sexually Exploited Children and Young People, said: "As always, our concerns lie with the young people who have been victims and (we) are very pleased to see a complete multi-agency team approach to assisting the recovery of the young people.
"The experience of our members in the network is that both victims and offenders come from a wide range of cultural and social backgrounds."
Jon Brown, of the NSPCC, added: "Trafficking is a major problem which requires urgent action and today's arrests show the police are taking a proactive approach, which is good news. Hopefully the children involved will get the protection and counselling they need.
Later, police said a 13th person had been detained this afternoon in connection with the investigation.
The details of those arrested are:
:: A 31-year-old man, arrested on suspicion of causing prostitution of girls under the age of 18, rape, and administering drugs with intent to commit rape;
:: A 29-year-old man, arrested on suspicion of causing prostitution of girls under the age of 18;
:: A 30-year-old man, arrested on suspicion of causing prostitution of girls under the age of 18, rape, and administering drugs with intent to commit rape;
:: A 31-year-old man, arrested on suspicion of sexual activity with a child;
:: A 32-year-old man, arrested on suspicion of causing prostitution of girls under the age of 18 and rape;
:: A 26-year-old, arrested on suspicion of rape and grooming;
:: A 34-year-old man, arrested on suspicion of causing prostitution of girls under the age of 18;
:: A 23-year-old man, arrested on suspicion of sexual activity with a child and grooming;
:: A 37-year-old man, arrested on suspicion of causing prostitution of girls under the age of 18, rape, and administering drugs with intent to commit rape;
:: A 37-year-old man, arrested on suspicion of causing prostitution of girls under the age of 18;
:: A 21-year-old man, arrested on suspicion of causing prostitution of girls under the age of 18;
:: A 34-year-old man, arrested on suspicion of causing prostitution of girls under the age of 18 and rape;
:: A 26-year-old man, arrested on suspicion of sexual activity with a child.
"Thames Valley Police is expecting to extend the custody for some of the suspects which will keep them detained until tomorrow," a force spokesman said.
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