Pavel Durov, the Russian-born billionaire founder and owner of the Telegram messaging app, was arrested at Le Bourget airport outside Paris shortly after landing on a private jet late on Saturday and has been placed in custody, three sources have said.

The arrest of the 39-year-old technology billionaire prompted a warning from Moscow to Paris on Sunday that he should be accorded his rights and criticism from X owner Elon Musk who said that free speech in Europe was under attack.

There was no official confirmation from France of the arrest, but two French police sources and one Russian source who spoke on condition of anonymity said that Durov was arrested shortly after arriving at Le Bourget airport on a private jet from Azerbaijan.