Four Waterloo Region residents are among nine people facing charges in connection with allegations that a seven-year-old girl was made available for sexual services through an online classified website.

Hamilton Police say their investigation into the case began in May with a tip from the Hamilton Catholic Children’s Aid Society that a young girl claimed she was being molested by her mother’s boyfriend.

A Hamilton man was arrested at that time on offences including nine charges of sexual assault and 10 charges of making child pornography.

Another Hamilton man was arrested about two weeks later, on similar charges.

Arrests continued in the summer, as the investigation moved into Waterloo Region.

A 38-year-old Waterloo man was arrested July 14 on two counts apiece of making and distributing child porn, as well as sexual assault and sexual interference.

On Aug. 9, a 48-year-old Waterloo woman was arrested on charges of sexual assault, sexual interference, and making and possessing child pornography.

The most recent of the nine arrests occurred Nov. 7, when a 35-year-old Waterloo man was taken into custody on charges of making and possessing child pornography.

Also charged in connection with the case was Geoffrey Burnet – a 48-year-old Kitchener man who was arrested in September on unrelated charges of sexual interference and invitation to sexual touching.

Detectives say they later linked Burnet to the seven-year-old girl, and laid charges of making and distributing child pornography against him.

Burnet previously worked for the Upper Grand District School Board, as well as schools in the Toronto and Hamilton areas.

At a Thursday morning news conference, Hamilton Police Det. Sgt. David Dunbar said that the seven-year-old girl was “being made available to be sexually assaulted by others through Craigslist,” and that some of the people arrested were “exchanging child pornography amongst each other.”

Among the people arrested, police say, are the girl’s mother and the mother’s boyfriend.

Police say they have seized more than 100 computers and electronic devices in connection with the investigation, which has been dubbed Project Links.

With reporting by Abigail Bimman