The star of a film about prostitution in Morocco said Thursday she had been abducted and savagely beaten for helping shine a light on an issue long taboo in the Muslim country.

Moroccan actress Loubna Abidar, 30, who plays a prostitute in "Much Loved", said she was dragged off the street and into a car in Casablanca last week by three young men and beaten, then mocked by police and hospital doctors when she turned to them for help.

"It was a terrible night. The doctors to whom I went for help and the police officers at the station laughed at me. I felt incredibly alone... (until) a cosmetic surgeon agreed to save my face," she wrote in the French daily Le Monde.

"They insulted me because I am a free woman. There is a proportion of the population in Morocco who are threatened by liberated women, by gays, by the desire for things to change," she added, in an article headlined, "Why I Left Morocco".

"Much Loved", which shows how young girls are often tricked into sex work, was banned in Morocco the day after its premiere at the Cannes Film Festival in May.

The government claimed the movie was an affront to "the moral values and dignity of Moroccan women, and is a flagrant attack on the kingdom's image".

The actress and the film's director, Nabil Ayouch, have since become the victims of a hate campaign on social media.

Abidar was picked out for abuse after she won best actress at the Angouleme festival of francophone film in August. Her Tunisian mother is also Jewish.

"'Much Loved' annoys people because it talks about prostitution, which is officially banned in Morocco, and because it gives a voice to women who have never been heard," Abidar said.

- Police 'happy I was beaten' -

The actress posted a video of her cut and badly-bruised face on Facebook after the attack, and demanded to be allowed to talk to the king, Mohammed VI, threatening to seek asylum in France if he did not see her.

After flying to Paris at the weekend she withdrew the threat and took down the video, claiming she had posted it in "anger... at the police who were happy to see me smashed up".

Casablanca police denied her version of events at the station in a statement, according to the website of the TelQuel weekly, with officers threatening to bring a defamation action against her for her claims.

"It is what you would expect," the actress told Le Monde. "If you accuse them they threaten to put you in prison to scare others."

The film weaves together the stories of four prostitutes in Marrakech and was warmly reviewed after it was released in France and Belgium in September.