A medical evacuation flight carrying comatose Russian opposition leader Alexei Navalny—who is gravely ill after a suspected poisoning—has landed in Berlin, according to flight-tracking site Flightradar24, CNN reported.

The Kremlin critic was flown out of Omsk, Russia, on Saturday morning to receive treatment in the German capital city.

Navalny, a critic of Russian President Vladimir Putin, is in a coma after becoming sick from suspected poisoning on a flight to Moscow from the Siberian city of Tomsk, his spokesperson Kira Yarmysh said Thursday. The plane later made an urgent landing in Omsk, she added.

On Friday, Russian doctors treating the anti-corruption blogger gave his team permission to move him.