Pavel Durov, the billionaire co-founder and CEO of the popular Telegram messaging app, was detained on Saturday evening at Bourget airport near Paris, according to TF1 TV, which cited an unnamed source.
Durov had been flying on his private jet, TF1 reported on its website, noting that he was the subject of an arrest warrant issued in France.
The 39-year-old was reportedly traveling from Azerbaijan and was apprehended at around 8:00 p.m. local time.
Originally from Russia, Durov currently resides in Dubai, where Telegram is headquartered. He holds dual citizenship in France and the United Arab Emirates.
Forbes estimates Durov's net worth at $15.5 billion. He left Russia in 2014 after refusing to comply with demands to shut down opposition groups on his VK social media platform, which he later sold.
Telegram did not immediately respond to a request for comment from Reuters.
The Russian embassy in France is taking "immediate steps" to clarify the situation.
Durov, along with his brother Nikolai, launched Telegram in 2013, and the app now boasts around 900 million active users.
Telegram provides end-to-end encrypted messaging and allows users to create "channels" for quickly sharing information with followers.