Gardai say one man was arrested in Ireland as part of an international investigation into child abuse.

The probe involved several counties and has resulted in nearly 400 children being rescued and hundreds of people being arrested worldwide after the investigation in Canada.

Police launched the investigation in November 2010 when about 200,000 explicit images of children were found at a house in Brantford, near Toronto.

Detectives said a Toronto man was later found running a website that allowed users to purchase pornographic videos of children.

The site, which allegedly offered digital downloads and a mail order service, is said to have made more than €2.9 million.

Reporter Dominic Waghorn said "What's extraordinary is that this man's alleged business appears to have been conducted out in the open. The website was described by people who saw it before it was shut down...as looking rather like Amazon".

"There was a legal page saying that everyone pictured in the images was of the right legal age. The police in Canada will have to prove that, under Canadian law, these images were made not for artistic merit but for sexual gratification".

"However, they've said that some of the images they found among several terabytes of data were horrific and the worst they'd ever seen" he added.

International cooperation

The results of the three-year investigation, known as Project Spade, were released by Brantford Police Service at a news conference.

A spokesman said 339 people had been arrested around the world, with 386 children rescued from child exploitation.

The investigation involved dozens of countries, including Ireland, the United States, Greece, Norway, Hong Kong, South Africa, Australia, Spain and Mexico.

A man arrested over the 2010 haul of pornographic photos, who was charged and released on bail at the time, was revisited by police when they received information about an alleged purchase of indecent images.

He was subsequently charged with accessing and possessing indecent images of children and two counts of breaching bail conditions and jailed last June.

Brantford Police Service did not release specific details of any of the other arrests.