The acutely-ill Russian opposition leader Alexei Navalny is being flown from Siberia to Germany for treatment.
He fell into a coma after drinking what his supporters suspect was poisoned tea; they accuse the authorities of trying to conceal a crime.
Doctors treating him in Omsk had insisted on Friday that he was too ill to be moved.
But they later said his condition was stable enough for the flight. His wife Yulia is travelling with him.
A medical evacuation flight, paid for by the German NGO Cinema for Peace, is taking Mr Navalny to Berlin, where he will be treated at the Charité hospital.
“Alexei’s plane has taken off for Berlin,” his spokeswoman Kira Yarmysh tweeted on Saturday morning. “Massive thanks to everyone for their support. The struggle for Alexei’s life and health is just beginning,”
Ms Yarmysh earlier said it was a pity doctors had taken so long to approve his flight as the plane and the right documents had been ready since Friday morning.
Mr Navalny fell ill during a flight from Tomsk to Moscow on Thursday, and his plane made an emergency landing in Omsk. A photograph on social media purported to show him drinking from a cup at a Tomsk airport cafe before the flight. His team suspects a poisonous substance was put in his tea.
Disturbing video appeared to show a stricken Mr Navalny howling in agony on the flight. Passenger Pavel Lebedev said he heard the activist “screaming in pain”.
What the doctors said on Friday
The head doctor at the hospital where Mr Navalny was being treated in Omsk, Alexander Murakhovsky, warned late on Friday that doctors did not recommend flying, “but his wife insists on her husband being transferred to a German clinic”.
“The patient’s condition is stable,” deputy chief doctor Anatoly Kalinichenko was quoted as saying by the Interfax news agency.
Mr Navalny is in an induced coma, and his condition is reported to be stable.
“As we’re in possession of a request from relatives to permit him to be transported somewhere, we have now taken the decision that we do not object to his transfer to another in-patient facility,” Dr Kalinichenko said.
Doctors said earlier that no poison had been found in his body, suggesting his condition might be the result of a “metabolic disorder” caused by low blood sugar.
Health officials then indicated that traces of an industrial chemical had been found on his skin and hair. The local interior ministry told the Rapsi legal news agency thatthe chemical was usually included in polymers to improve their elasticity, but its concentration was impossible