London, Oct 15 (IANS): A paedophile, who groomed vulnerable adolescent boys across Britain along with an accomplice through social networking sites and later recorded their sexual abuse, has been found HIV positive.

The duo used to target and befriend vulnerable teenage boys using social networking sites such as Facebook and Bebo, along with specialist gay dating websites.

Anthony Marsh, 53, and Lee Davis, 39, have already admitted to dozens of sex offences against boys between the ages of 13 and 17, The Indepenedent reported.

After grooming their victims, salesman Marsh, who has the disease that causes AIDS, and Davis, an unemployed, would meet the teenagers and sexually abuse them.

Marsh and Davis, who live near South Yorkshire's Doncaster town, are married and have their own families.

"Both were family men, both leading double lives," the detective said.

South Yorkshire police said Davis would film teenagers at his home or inside his van. Officers believe that Marsh distributed some of the footage he recorded himself over the web.

The pair used to spend hours online gaining the trust of their victims, said a police official.

Aside from the string of offences that the two already admitted to at the Sheffield Crown Court last month, detectives believe there may be even more victims, who are yet to be traced.

The Crown Prosecution Service decided it would not proceed with a small number of additional allegations denied by the pair.

The offences took place in an eight-year period from 2005 until June this year.

Marsh and Davis will be sentenced in December.