The O.C. actor Mischa Barton has revealed that a former boyfriend secretly filmed her having sex with him and has tried to sell the footage.

Barton, 31, attended a news conference with her lawyer Lisa Bloom, who described the videos as "revenge porn".

The footage, which contains naked and sexually explicit images of the London-born star, were allegedly recorded by hidden cameras set up by an ex-boyfriend in the last 12 months.

Police are investigating and a court in Los Angeles has blocked any sale or showing of footage or images from the videos.

Barton said she was speaking out about the criminal investigation and court order for both herself and other women.

"Revenge porn is a very common crime... it's scary, even for a celebrity, to stand up like this but it's important for girls and women to stand up for our rights," Bloom added.

It is illegal to make a recording that violates the privacy of others without their consent.

In 2013, university student Michael Piznarski, 23, was jailed in New York for secretly recording his girlfriend performing a consensual sex act with him and then threatening to make the video public.

The covert filming of consensual sex is illegal in the UK and anyone convicted could face up to two years in prison.

In 2010, former BBC producer Benjamin Wilkins was jailed for eight months and ordered to sign the Sex Offender Register for 10 years for secretly filming women he had sex with in his flat.

More than 200 Britons have been prosecuted for revenge porn since the implementation of laws to tackle the crime were rolled out in April 2015, an official report revealed last year.

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