By Fabrizio Bensch and Martin Schlicht
BERLIN (Reuters) - Gravely ill Kremlin critic Alexei Navalny was evacuated to Germany for medical treatment on Saturday, flown out of the Siberian city of Omsk in an ambulance aircraft and taken to a hospital in Berlin.
There was no word yet from the Charite hospital on his condition but the founder of the activist group that arranged the flight called Navalny's health condition "very worrying".
A long-time opponent of President Vladimir Putin and campaigner against corruption, Navalny collapsed on a plane on Thursday after drinking tea that his allies believe was laced with poison.
Medical staff at the hospital in Omsk said on Friday evening after clearing Navalny to be flown out that he was in an induced coma and his life was not in immediate danger.
The air ambulance, arranged by the Cinema for Peace Foundation, flew to Berlin early on Saturday and Navalny, 44, was rushed to the Charite hospital complex.
The hospital said in a statement it would provide an update about his condition and further treatment once tests have been completed and after consulting with his family.
A spokeswoman for Charite said later that it was unlikely that the hospital would give a statement on Navalny over the weekend.
Cinema for Peace founder Jaka Bizilj, speaking to reporters outside the hospital, said "his health condition is very worrying".
"We got a very clear message from the doctors that if there had not been an emergency landing in Omsk, he would have died," said Bizilj, adding that it would be up to doctors and Navalny's family to provide further information on his condition.
Bizilj, a Slovenian-born activist and filmmaker, was earlier quoted by Bild tabloid as saying Navalny's condition was stable during the flight and after landing.
Kira Yarmysh, Navalny's spokeswoman, said on Twitter that "This is another proof that nothing was preventing Navalny from being transported, and it was necessary to do so as early as possible."
German doctors flew to Russia on Friday to evacuate Navalny at the request of his wife and allies who said that the hospital treating him was badly equipped.
But there was then a delay flying him out as the Omsk hospital initially said his condition meant he could not travel.
The Omsk doctors later said they had no objections after the German doctors deemed him fit for travel.
Navalny's wife, Yulia, sent a letter to the Kremlin directly appealing for it to intervene and grant permission for him to be flown out.
Navalny's allies have said they feared authorities in Russia might try to cover up clues as to how he fell ill.
The doctors in Omsk said on Saturday they were ready to share all information they have with the German clinic.
Two years ago, Pyotr Verzilov, another anti-Kremlin activist and a member of the Pussy Riot art collective, was treated at the Charite hospital after he was poisoned in Moscow.
Navalny has been a thorn in the Kremlin's side for more than a decade, exposing what he says is high-level graft and mobilising crowds of young protesters.
He has been repeatedly detained for organising public meetings and rallies and sued over his investigations into corruption. He was barred from running in a presidential election in 2018.
(Additional reporting by Reuters TV, Fanny Brodersen, Christoph Steitz, Maria Sheahan, Ekaterina Golubkova, Andrey Kuzmin, Susanne Neumayer-Remter; Editing by Frances Kerry)