Five people have been arrested over offences in Wakefield including assault and false imprisonment as police issued a warning to so-called 'paedophile hunter' groups.
The three men and two women were taken into custody in Leeds relating to alleged offences that occurred in Wakefield on August 11 last year, and on January 13 in Leeds this year.
They have since all been released on bail and enquiries are ongoing.
A police spokesman said: "Protecting children from abuse is a top priority for West Yorkshire Police and we would encourage members of the public to report any concerns about illegal internet activity of potential child abusers to us so that we can deal with it.
"We are also concerned about the activities of online child abuse activist groups and their exposure activity in confronting persons they have identified.
"We urge members of such 'exposure' groups not to carry out this activity and instead to report suspected offences in West Yorkshire to the force via 101 or the independent Crimestoppers charity on 0800 555 111."
The hunter groups often pose as children online to lure paedophiles to meeting points before turning up in numbers to confront them.