A CIVILIAN computer expert charged with downloading child pornography while working at a police headquarters revealed yesterday that he is a former MI6 agent.

Alan Coates claims his work for Cleveland Police - which now includes the bugging of police officers suspected of criminal links - made him a target for many people.

Denying 15 specimen charges of making an indecent photograph of children, Coates claims he is the victim of a highly sophisticated frame-up which saw the images planted to discredit him.

His past as a secret agent emerged at Newcastle Crown Court, where a statement agreed by both defence and the Crown was read to jurors.

It revealed Coates, 52, joined the British Army in 1967, where he trained in surveillance techniques with armed forces and the American Special Forces carrying out increasingly sensitive work for various government agencies.

The statement, read by Coates's barrister, Beatrice Bolton, added: "He transferred to MI6 and while working for them he was involved in very sensitive work. He was subject to the Official Secrets Act and positively vetted on at least three occasions."

While posted in Saudi Arabia, Coates fell for a female computer expert. They married and he left MI6 for a post with an electronics company in Tucson, Arizona, where he also carried out sensitive surveillance work.

He returned to Britain with his wife and two children in 1988 and secured the job at Cleveland Police. His work includes the "sweeping" of rooms for security, the bugging of fellow officers and overseeing the introduction and testing of a multi-million-pound communications system.

A world renowned expert on moths, he lives at Forest Lodge, Redford, County Durham, on the Hamsterley Forest nature reserve.

The court heard how in November 1998, officers discovered hundreds of child porn images had been downloaded from the Internet. Coates's home was searched and more pornographic images were found.

Asked by police how the images could have got onto his computers, he said: "I have tried to figure this through myself. I'm sure you can understand it is driving me crazy trying to figure it out. The whole thing is an utter bloody mystery, it is freaking me out"

Asked whether he was suggesting a conspiracy theory, Coates told police: "That's the only thing I can come up with in my mind."

Giving evidence, Coates denied downloading porn and said that as a computer expert, he could have easily encrypted such sensitive images to make sure only he could access them.

The trial continues