Ontario police say they have arrested 80 people as part of a sweeping investigation into internet child pornography in the province.

Ontario Provincial Police said Thursday the investigation involved 274 charges against 80 people, including one youth.

Charges include sexual assault, possession of child pornography, making child pornography, distributing child pornography and accessing child pornography. Police say 20 victims have been identified.

Police said Thursday they also secured the safety of nine people working in the sex trade as minors or against their will.

OPP worked with several security agencies including the U.S. Department of Homeland Security to make the arrests.

OPP says no arrests were made in the U.S.