Four men have killed themselves after being targeted in a new and fast-growing sex blackmail scam.

Victims are being lured into exposing themselves or committing sex acts online by pretty young women after accepting their friendship requests on social networking sites.

They then face payment demands of hundreds of pounds - or threats that recordings of their behaviour will be sent to family and friends whose contact details they have unwittingly given access to.

Martin Hewitt, of the National Police Chiefs' Council, said: "We started to see it emerging about 18 months ago.

"Last year we had about 300 offences recorded in the UK and we're now this year over 900, and I suspect there's a significant number that don't get reported because the crime is preying on people's embarrassment and their humiliation of being caught out doing something like this."


Image: Ronan Hughes was tricked into sending intimate photos of himself

Schoolboy Ronan Hughes, 17, was tricked into sending intimate photographs of himself, then faced a demand for £3,000 to avoid exposure.

He killed himself even though he had revealed the threat to his parents and police in County Tyrone, Northern Ireland.

Daniel Perry, from Dunfermline, also 17, took his own life after threats to reveal his compromising online conversations.

Police would not reveal details of the other two suicides, but said they were both within the past year and added there could be more.

Carpenter Jon Pearn, 58, from Plymouth, admitted exposing himself online to a girl who claimed her name was Angel, but then revealed she was a man and demanded money. He refused to pay.

Image: Criminals threatened to expose Daniel Perry's online conversations

He said: "To me it was just one big joke - I just didn't care what they were saying at me. They weren't going to bluff me.

"Even if I was happily married, which I'm not - I'm single, so it can't affect anybody.

"Even if I had thousands of pounds I wouldn't have paid them a penny. To me they're just sad little low-lifes. Trying to bleed innocent people.

"And then when I went to the police I was gobsmacked when the police lady told me how many people had been in just that month - 19 people in that police station alone."

Organised crime groups in the Philippines, Morocco and Ivory Coast were discovered running many of the sextortion scams, some using British girls.

Most of the UK victims are men aged 18-24, the eldest was 82 and the youngest 14. Some women have also been targeted.

Police have issued advice to victims, urging them not to pay or panic, but to shut down their social media accounts and report what has happened.

Senior officers insisted they will investigate and will not judge victims' behaviour.

Roy Sinclair, from the National Crime Agency's (NCA) anti-kidnap and extortion unit, said: "There is huge under-reporting of these kinds of offences, often because victims feel ashamed or embarrassed, but of course criminals are relying on that reaction in order to succeed.

"This is why we are launching this new campaign. We want victims and potential victims to know how they can protect themselves and to understand what to do if they are targeted.

"This is still a relatively new and emerging crime type, so the NCA and police are working with the Home Office to get a more accurate picture of the true scale."

The campaign includes a film aimed at helping victims to recognise an approach and providing online advice.