The founder and CEO of messaging app Telegram, Pavel Durov, was arrested at a French airport outside Paris on Aug. 24 evening.

According to Reuters, French media outlet TF1 TV said on its website that an arrest warrant in France targeted the Russian-French billionaire as part of a preliminary police investigation.

French media outlets, BFM TV and TF1 TV, both said that the investigation was focused on Telegram's lack of moderators, which the police considered allows criminal activity to go undeterred on the platform, citing unnamed sources.

BBC reported that Russia's embassy in France is taking "immediate steps" to clarify the situation.

The Guardian, reporting off Reuters, understood that Durov was travelling from Azerbaijan.

Durov, 39, was expected to appear in court on Sunday.

With almost one billion users, Telegram is one of the major social media platforms after Facebook, YouTube, WhatsApp, Instagram, TikTok, and WeChat, said Reuters.

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