Police in West Yorkshire have arrested 55 men over child sex abuse dating between 2002 and 2009.
The men were arrested at addresses in Dewsbury, Batley and Bradford over the last few months.
All have subsequently been released under investigation.
Detective Inspector Ian Thornes, leading the investigation, said: “This investigation demonstrates the force’s ongoing commitment to the investigation of both current and non-recent sexual offences against children.
“Child sexual abuse and exploitation is an abhorrent and heinous crime and one which affects some of the most vulnerable people in our society.
“We have teams of specialist safeguarding units across each District in West Yorkshire, which include police officers dedicated to dealing with both current and non-recent child abuse and child sexual exploitation.”