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 billionaire was arrested under a warrant for offences related to the popular messaging app. The investigation is reportedly about a lack of moderation, with Mr Durov accused of failing to take steps to curb criminal uses of Telegram.
The app is accused of failure to cooperate with law enforcement over drug trafficking, child sexual content and fraud. Telegram has previously denied having insufficient moderation.
Read more: www.bbc.com