It was an international effort that spanned more than 50 countries, and has since resulted in at least 348 arrests worldwide.
The child pornography investigation that would come to be known as Project Spade all started with a focus on one man living in Toronto.
The officer in charge of the child exploitation unit at the Toronto Police Service, Inspector Joanna Beavan-Desjardins, said undercover officers made contact with the man who was alleged to be sharing "very graphic" images of young children being sexually abused, back in 2010.
WATCH: Toronto Police Service press conference
"The investigation revealed that this individual was running an exploitation movie, production and distribution company," she said.
"Customers around the world could arrange to have movies sent to them, through the mail or through the internet."
The movies were sent from Canada to addresses around the world, including the US, Sweden, Norway, Hong Kong and Australia.
In May 2011, Canadian police services obtained a search warrant for a property in Toronto containing thousands of videos and a number of hard drives. It took four days to log all the evidence.
Officers allege they found "hundreds of thousands" of images and videos detailing "horrific" sexual acts against children at the home of 42-year-old Brian Way, said Ms Beavan-Desjardins. "Some of the worst they have ever seen."
Mr Way has been charged with 24 offences, including numerous child pornography charges, proceeds of crime offences and instructing a criminal organisation.
He allegedly paid people to film children in countries within eastern Europe, to produce movies which he would then sell.
Police then went after the customers, using Interpol and other agencies to hunt those in other countries.
"This investigation was dubbed Project Spade, and its success has been extraordinary," said Inspector Beavan-Desjardins.
At least 386 children to date have been rescued from sexual abuse as a result of the investigation.
Arrests by country
Canada - 108
Australia - 65
USA - 76
Other - 99
Arrests by profession
School teacher - 40
Doctor/nurse - 9
Law enforcement personnel - 6
People who volunteered with children - 32
Pastors or priests - 9
Foster parents - 3
View more: Project Spade infographic
