DETECTIVES in York have uncovered some of the most depraved images yet seen in the UK as part of an international investigation into child pornography.

The Evening Press can today reveal that 15 officers at Fulford Police Station are playing a key role in cracking a global paedophile ring based in Germany.

Many of the images have proved so extreme that the York investigators have been stopped from viewing them, according to the city's police commander, Chief Superintendent John Lacy.

The officers were also offered counselling to help them cope with their highly distressing task.

Chief Supt Lacy said special computer technology was being used to isolate the faces of victims.

Experts from the Metropolitan Police and Greater Manchester Police have also been brought in to assist with the investigation.

The global investigation started in July 2002 when police discovered the email addresses of 1,000 pornographic "trading partners" after raiding the apartment of a 26-year-old man in Magdeburg, Germany.

An electronic trail led to York where officers set up Operation Mercury, the biggest child pornography investigation ever to take place in North Yorkshire.

Much of the information was uncovered after a court decision forced an internet service provider to turn over evidence it had on the suspects, including 38,000 email addresses.

Last week, up to 1,500 German police officers raided 500 houses after a year-long investigation into child pornography.

More than 500 suspects have since been questioned and 745 computers, 35,500 compact discs, 8,300 computer discs and 5,800 videos have been seized.

The National Crime Squad and the National Criminal Intelligence Service first received details on 22 UK-based suspects late last year and further details were sent out to individual forces a fortnight ago.

A North Yorkshire police press officer today confirmed that a York man had been arrested and charged in connection with Operation Mercury.

Updated: 10:56 Wednesday, October 01, 2003