Telegram chief executive Pavel Durov has been arrested by French police at an airport north of Paris.
Mr Durov was detained after his private jet had landed at Le Bourget Airport, French media reported.
According to officials the 39-year-old had been arrested under a warrant for offences related to the popular messaging app.
Russia's embassy in France is taking "immediate steps" to clarify the situation, according to Russia's TASS state news agency.