Twelve men have been arrested on suspicion of a string of child exploitation offences including causing the prostitution of young girls, trafficking, grooming and rape.
Detectives are investigating the cases of 24 girls aged between 11 and 16 in Oxford.
The men, aged between 21 and 37, are being held in police custody.
Detective Superintendent Rob Mason, of Thames Valley Police, 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."
The offending is believed to span more than a six-year period.
Councillor Louise Chapman, Cabinet Member for Children Young People and Families from Oxfordshire County Council, said: “Thames Valley Police and the Oxfordshire County Council’s children’s social care team linked up swiftly when it became apparent that it would be dealing with an investigation that centred on child exploitation.
“This prompt action allowed children’s social care workers to work in close partnership with Thames Valley Police, with officers from the county council being seconded to the police, working from police premises.
“The county council has assisted in what has been a complex investigation leading to today’s events. Its focus has been, and will continue to be, on the care for alleged victims.
“Thames Valley Police has demonstrated in conducting this investigation that it is not prepared to tolerate child exploitation in Oxfordshire. The county council feels sure it is speaking for the whole community in expressing total support for the police in this regard.”