The head of Telegram, Pavel Durov, has been charged by the French judiciary for allegedly allowing criminal activity on the messaging app but avoided jail with a €5m bail.

The Russian-born multi-billionaire, who has French citizenship, was granted release on condition that he report to a police station twice a week and remain in France, Paris prosecutor Laure Beccuau said in a statement.

The charges against Durov include complicity in the spread of sexual images of children and a litany of other alleged violations on the messaging app.

His surprise arrest has put a spotlight on the criminal liability of Telegram, the popular app with around 1 billion users, and has sparked debate over free speech and government censorship.