Russian artist, partner held over sex tape that felled Macron's favoured candidate for Paris mayor

French police held a Russian activist and his girlfriend for questioning on Sunday over a sex tape released online that brought down President Emmanuel Macron's favoured candidate for Paris mayor.

Pyotr Pavlensky has said he leaked the video that forced the centrist ruling party's Benjamin Griveaux to bow out of the running for mayor in next month's election.

The 35-year-old artist, who received asylum in France in 2017 after several radical protests in Russia, was arrested on Saturday in connection with a fight at a New Year's party.

On Sunday, however, police turned their attention to the images posted online this week of a man presented as Griveaux masturbating, coupled with racy text messages purportedly sent by the politician.

The video prompted Griveaux, a married father of two, to call off his mayoral campaign, citing the need to protect his family from scandal.

Pavlensky's girlfriend Alexandra de Taddeo, believed to have been the recipient of the video, was arrested on Saturday evening on charges of invasion of privacy and publishing images of a sexual nature without consent.

The 29-year-old Frenchwoman was being questioned on Sunday at the headquarters of the criminal police in Paris.

On Friday, Pavlensky told AFP that he had posted the footage online in order to expose the "hypocrisy" of 42-year-old Griveaux and planned to post more material on a newly created "political porn platform".

Griveaux "is someone who constantly brings up family values, who says he wants to be the mayor of families and always cites his wife and children as an example. But he is doing the opposite," Pavlensky told France's Liberation daily.

Griveaux's lawyer, Richard Malka, hit back on Sunday, accusing "pseudo artists" of giving "morality lessons".

Former government spokesman Griveaux is the first senior French politician to pull out of a campaign over a sex scandal, marking a turning point in the country's traditionally permissive attitudes towards politicians' private lives.

French media and politicians from across the spectrum have portrayed the 42-year-old, who has filed a formal complaint for invasion of privacy, as a victim.

"Everyone has the right to their secret garden," the speaker of the National Assembly, Richard Ferrand, told Le Journal du Dimanche newspaper.

Malka hinted at a political set-up, saying he suspected Pavlensky "did not act alone".

- SCRAMBLE TO FIND SUCCESSOR -Griveaux's fall has left Macron's Republic on the Move (LREM) party scrambling to find a replacement candidate for the job of Paris mayor a month before the vote.

Griveaux's campaign had already been in trouble before the sex tape emerged, dragged down by a rebel candidacy from fellow Macron supporter and star mathematician Cedric Villani.

Recent polls had placed the official LREM candidate third, behind incumbent Mayor Anne Hidalgo, a Socialist, and conservative candidate Rachida Dati.

Among the names floated as possible replacements for him include Health Minister Agnes Buzyn and Education Minister Jean-Michel Blanquer.

Deputy Transport Minister Jean-Baptiste Djebbari said the new candidate would be announced on Sunday evening.

- RAGING AGAINST 'APATHY' -
Pavlensky has a track record of causing outrage.

In 2013, he nailed his scrotum to Red Square to protest against the "apathy and political indifference" of Russian society.

Two years later, he doused the doors of the FSB secret police headquarters with petrol and set them on fire.

In October 2017, he set fire to the offices of the Bank of France on Place Bastille, site of the attack on an infamous prison at the start of the French revolution in 1789.

He was given a short jail sentence over that incident.

The December 31 incident, over which he was arrested on Saturday, involved a fight at a New Year's Eve party in Paris which he is accused of pulling a knife.

Two guests at party suffered knife wounds, according to the Mediapart investigative website