Russian opposition leader Alexei Navalny is in a coma in a Berlin hospital, and Germany has revealed he was poisoned by a Novichok nerve agent.   He was taken ill on board a return flight from Siberia to Moscow and the plane made an emergency landing in Omsk. Two days later Russian officials were persuaded to let him be airlifted to Germany. AFP Russian has pieced together the story of how flight attendants and medics fought to save his life over the skies of Siberia. This is the dramatic two-hour timeline of that perilous journey. How the morning unfolded It was 20 August, and Alexei Navalny was taking an S7 airlines flight from Tomsk to Moscow. He didn't eat or drink anything all morning - apart from a cup of tea he bought at Tomsk Bogashevo airport, according to his press secretary Kira Yarmysh. Another passenger on the flight, Ilya Ageev, saw Mr Navalny drinking the tea about an hour before the plane was due to take off. The Kremlin critic was smiling and joking with fellow passengers who recognised him.