(Bloomberg) -- Sex-related extortion rose 30 percent in the U.K. in the last year alone, the National Crime Agency said, as young men are increasingly targeted by female criminals.

The NCA recorded 1,700 cases in 2018, according to figures reported in the Sunday Times. That’s a jump from 1,300 in 2017, and “a few hundred” more than were reported five years ago, the newspaper said.

The nature of the extortion -- which the newspaper dubbed sextortion -- seems to be changing, the Times said. Young men are the main victims, it said, and are increasingly being targeted by individuals, especially by females. Victims are befriended on dating apps including Tinder and Grinder, and then blackmailed when they share photos or information that may be embarrassing.

The newspaper gives examples of women demanding money from men by using threats to report their requests for explicit photos to police or their sexual practices to family members. The criminals are often acting alone, and can demand as little as 100 pounds ($130), the Times said.

In previous NCA data, investigators found that the crimes were mostly carried out by overseas organized groups, targeting young males and an increasing number of British Armed Forces.

A lot of the cases are unreported, the NCA said, and these numbers don’t give the true size of the problem. In last year’s report, the NCA said sextortion cases were linked to five suicides.

To contact the reporter on this story: Allegra Catelli in London at acatelli@bloomberg.net

To contact the editors responsible for this story: Tom Contiliano at tcontiliano@bloomberg.net, Christopher Elser, Amanda Jordan

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