A series of dawn raids this morning has resulted in the arrest of 40 paedophiles after police used specially developed software to track the distribution of indecent images of children.

The raids, carried out at 7am this morning, involved 25 police forces around the country, simultaneously making arrests in Avon and Somerset, Cheshire, Cleveland, Derbyshire, Dorset, Essex, Greater Manchester, Hertfordshire, Humberside, Kent, Leicestershire, Lothian and Borders, Merseyside and London. The 40 arrests were the result of a three-month investigation.

Operation Appal was run as a joint operation between the Greater Manchester Police with help from content filtering developer, SurfControl.

SurfControl teamed up with the GMP's Obscene Publications Unit last year, to provide them with tailored software to help the Unit's officers locate and track internet users involved in possessing and distributing images of child pornography.

The company claims that the custom software boosted the Unit's effectiveness, where previously 60 man-hours of internet checking were needed to produce 16 suspects.

SurfControl's chief executive, Steve Purdham, said: "This joint project shows that the tools are available to help safeguard internet users - whether at home or in the workplace - against inappropriate or illegal material, and also against individuals with indecent or malicious intent."