Police across Canada have arrested more than 50 people on charges of sexual assault, sexual interference and possessing, making and distributing child pornography.

Project Salvo, the largest-ever co-ordinated investigation of Internet-based child sexual abuse in Canada, was led by the National Child Exploitation Coordination Centre (NCECC).

The operation, involving the RCMP and 35 police departments, focused on an Internet ring in which participants exchanged child porn online.

At a press conference Thursday, RCMP Sgt. David Fox, with the NCECC, said police issued 71 search warrants and arrested 57 people in total.

Fox said police have laid more than 100 criminal charges, seized 130 computers, dozens of computer hard drives, and thousands of computer storage devices and discs.

"Additional searches, arrests and charges are anticipated in the coming weeks," he said.

The operation took three months to complete and police used advanced investigative tools and technology to track the suspects online.

Fox, in an interview with CTV Newsnet after the press conference, said child-porn addicts have a "need-driven behaviour."

"They're going to act out on their fantasies," Fox said. "These people that are involved in this are offending and committing sexual assaults against young children in our own backyards, in the communities that we live in."

RCMP Supt. John Bilinski, who is in charge of the NCECC, said Internet-based child sexual abuse crosses many jurisdictions.

"This project goes a long way in demonstrating that Canada has a multi-pronged response strategy to Internet-facilitated child sexual exploitation," Bilinski said at the press conference.

He called on citizens to actively report crimes if they suspect someone is involved in exploiting children.

"I can assure you that we will continue to put every effort towards protecting children in Canada and abroad," he said.

Lianna McDonald, with the Canadian Centre for Child Protection (CCCP), said secrecy is the cornerstone of child sex abuse.

"No longer can we doubt that we have a growing problem in this country surrounding the sexual exploitation and sexual abuse of children," McDonald said.

"Today's announcements underscore the need for Canadians to wake up and recognize that this growing problem is affecting all of our children."

The CCCP operates cybertip.ca, a website where Canadians can report online sexual exploitation of children.

Since launching in 2002, McDonald said the website has received more than 30,000 tips.