OTTAWA — A national tipline for reporting online child sexual exploitation will be officially launched Monday, almost two years after the federal Liberals promised a strategy to counter Internet crimes against children.

The project grew out of an online service created by Child Find Manitoba in September 2002.

Called cybertip.ca, the Manitoba-based service was the first online service in Canada to report instances of child exploitation.

The website collects complaints and incident reports about child sexual exploitation or luring on the Internet and forwards the most serious to appropriate law enforcement agencies.

The pilot project, created with $530,000 from Ottawa and $72,000 from the Manitoba government, has gained an international reputation through word of mouth.

Within two years of its inception, it had been credited with several cases of police charging offenders with producing and distributing online child pornography.

The tipline has proven to be a "valuable additional tool'' for law-enforcement agencies, said federal Public Safety Minister Anne McLellan.

She acknowledged that not all of the tips collected in the pilot effort yielded useful information.

"Some of it leads nowhere,'' McLellan said Friday. "But in fact in other circumstances it provides valuable information in terms of individuals who are in possession of pornography, maybe in the distribution of it, the use of it, the production of it.''

Just before the June federal election, cybertip.ca got a financial boost when Prime Minister Paul Martin announced an extra $42 million over five years to help fight Internet-based child exploitation.

Most of the money was earmarked for the RCMP, but some of it went to cybertip.ca, helping to double its budget to about $1 million annually.

The money would be used to market the website across Canada, Lianna McDonald, executive director of Child Find Manitoba, said then.

McDonald and McLellan will be among the politicians, law enforcement officials and child advocates at the Monday launch.

The connection between the Internet and child abuse was framed starkly last June, when Michael Briere, a software programmer with no previous criminal record, pleaded guilty to the abduction, rape, murder and dismemberment of Holly Jones.

Briere linked the crime to the fact he had been downloading child porn from the Internet the night he abducted the 10-year-old girl in Toronto.

His admission sparked urgent calls for tighter federal law.

The timing couldn't have been better for giving the issue a high profile -- it was in the midst of a federal election campaign.

Federal child pornography laws have been a bone of contention for nearly a decade, pitting police and victims' rights advocates against civil libertarians and creative artists.

In July 2002, new laws came into force providing sentences up to 10 years for transmitting or posting child porn on the Internet, and five-year sentences for communicating over the net with a child for the purposes of sex acts.

On the other side of the coin, police forces have complained that lack of resources and court interpretations of child porn laws have made it difficult for them to pursue the more than 2,000 known Canadian purchasers of Internet child porn.

In its throne speech last February, the federal Liberal government said it was committed to upgrading child protection laws, including those regulating the Internet.

The previous Liberal government of Jean Chretien had introduced legislation in 2002 to tighten Criminal Code provisions against child pornography.

The bill finally passed the Commons in May 2004, but didn't clear the Senate in time to become law before Parliament was dissolved for the June election.

Meanwhile, Internet child pornography is flourishing.

In one of the latest cases -- just this week -- Ottawa police said they seized Internet software that contained potentially millions of pictures and videos depicting some of the "most heinous'' acts of child sexual abuse they had ever seen.

"It's the quantity of extremely young children who are depicted in these images and some of the most aggressive depictions of sexual abuse as opposed to sexual acts and sexual posing,'' Sgt. Sandra McLaren said.

Last October, a Quebec police official said that child pornography accounted for one-third of all Internet crimes investigated by Quebec provincial police.