Police forces across the UK have arrested 660 suspected paedophiles including doctors, teachers and former police officers in the biggest operation for more than a decade.

A paediatric doctor is amongst the suspects, as is a foster carer who was looking after a 12-year-old child at the time of the arrest.

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A third man is suspected of having more than a million indecent images of children, according to details released by the National Crime Agency.

Officers targeted people accessing child porn online, focusing on people who had unsupervised access to children in their line of work.

It has been reported that 431 children were identified as being 'at risk' of abuse and steps had been taken to protect them.

Phil Gormley, the director general of the NCA, told The Independent: “We cannot afford not to look under this stone. We knew that we were going to reveal volume."

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He went on: “It's a bit like a drugs problem. You need to look for it if you're going to find it.

“People are unlikely to report this type of crime, you're not going to have witnesses to it in the way that traditional crime types will.“

The NCA also revealed that, in the past 20 years, the number of images available has soared from an estimated 10,000 to tens of millions.

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John Carr, secretary of the UK Children’s Charities’ Coalition on Internet Safety, said: “[This operation] sends out a very clear warning to paedophiles and collectors of indecent images everywhere that the interest is increasingly become a very hostile environment for them.”

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