Pavel Durov, billionaire founder and CEO of the Telegram messaging app was arrested at the Bourget airport outside Paris on Saturday evening, TF1 TV and BFM TV said, citing unnamed sources.

Durov was traveling aboard his private jet, TF1 said on its website, adding he had been targeted by an arrest warrant in France as part of a preliminary police investigation.

TF1 and BFM both said the investigation was focused on a lack of moderators on Telegram, and that police considered that this situation allowed criminal activity to go on undeterred on the messaging app.

Telegram did not immediately respond to a Reuters request for comment. The French Interior Ministry and police had no comment.

TF1 said Durov had been traveling from Azerbaidjan and was arrested at around 20:00 (18:00 GMT).

Telegram, based in Dubai, was founded by Russian-born Durov, who left Russia in 2014 after he refused to comply with demands to shut down opposition communities on his VK social media platform, which he sold.

Durov, who is estimated by Forbes to have a fortune of $15.5 billion, said some governments had sought to pressure him but the app, which has now 900 million active users, should remain a "neutral platform" and not a "player in geopolitics."