An investigation into child pornography led Guelph Police to northern Ontario.

Police say they began their investigation last month when they were contacted by a concerned parent, and it eventually led them to arrest a 34-year-old Guelph man.

He faces a total of 13 criminal charges, including multiple counts of sexual assault, sexual interference, luring a child and making child pornography.

Also arrested was a 23-year-old Guelph man, who is charged with possession of child pornography and conducting a sexual offence against a child.

Further investigation led police to northern Ontario, where a 44-year-old North Bay man and 27-year-old Sudbury man were both arrested Thursday.

The North Bay man faces charges of accessing, distributing and possessing child pornography, while the Sudbury man is charged with two counts of luring a child, one count of possessing child pornography and other related offences.

Electronic equipment was seized from the accused.

Police know of three victims in this case, but believe there may be more victims and offenders than those of which they are currently aware.

Anyone with information is asked to contact Guelph Police at 519-824-1212 ext. 733, their local police service, or Crime Stoppers at 1-800-222-8477.