Alexei Navalny is a Russian opposition leader, politician, and anti-corruption activist. He was poisoned in August with a a Novichok nerve agent and flown to Germany to recuperate. He accuses Vladimir Putin of being behind the attack. Six days ago, he returned to Russia and was detained at the airport, and is at risk of prison sentences related to his stay in Germany and the activity of his anti-corruption organisation. There have been significant protests within Russia regarding Navalny's imprisonment.