Alexei Navalny , staunch critic of Russian President Vladimir Putin, was taken into custody Sunday after flying into Moscow, his first return to Russia since allegedly being poisoned by Kremlin agents.
Navalny's flight from Berlin was diverted from Moscow's Vnukovo Airport to nearby Sheremetyevo Airport right before landing, where police were waiting to detain Navalny without explanation.
His lawyer was not allowed to accompany him and his location is currently unknown.
Navalny's spokesperson, Kira Yarmysh, posted a video of the arrest online.
After treatment, Navalny participated in a sting operation where he was able to trick one of his alleged poisoners – a FSB agent working for the Kremlin – into confessing the details of the assassination attempt on his life.
Navalny has fiercely opposed Putin for years and has a substantial online following, with millions of subscribers on YouTube alone. He has encouraged Russians not to vote in elections, saying it only gives credence to the government's attempt to create the illusion of democracy.