The co-founder and chief executive of Telegram Pavel Durov was arrested at the Bourget airport outside Paris on Saturday.
Durov was travelling aboard on his private jet. Media reports said that he was targeted by an arrest warrant in France.
Durov was expected to appear in court on Sunday.
Born in Russia, Durov lives in Dubai, where Telegram is based, and holds the citizenship of both France and the UAE.
Telegram didn't comment on the incident.
Russia’s embassy in France said it is taking “immediate steps” to clarify the situation.
TASS reported there had been no appeal from Durov’s team to the embassy, but that it was proactively taking “immediate” steps.
Durov and his brother Nikolai founded the app in 2013 and it has almost 900 million active users.