Alexei Navalny, Voice Of Russia's Opposition, Is Hospitalized In Possible Poisoning

Alexei Navalny, Russia's most outspoken critic of President Vladimir Putin, is fighting for his life in a hospital, and his spokeswoman says she believes Navalny was poisoned as he was flying from Siberia back to Moscow.

Navalny is unconscious and on a ventilator, spokeswoman Kira Yarmysh, who had been traveling with the opposition leader, said via Twitter.

Navalny drank some tea at the airport in Tomsk, Yarmysh said, adding that he began feeling unwell shortly after his commercial flight took off. His deteriorating condition prompted the plane's pilots to make an emergency landing at Omsk, some 550 miles away.

A doctor who spoke to reporters at the hospital "said Navalny is in serious but stable condition in the intensive care unit," NPR's Lucian Kim reports. "But he said poisoning it poisoning is only one possible diagnosis."

The only thing Navalny drank before becoming sick was the tea, according to Yarmysh, who says she was with Navalny from early in the morning.