Story highlights Dissident vows to continue working for democracy

Kremlin denies connection to Kara-Murza's illness

Moscow (CNN) A critic of Russian President Vladimir Putin, who was hospitalized this month after suspected poisoning, has left the country to seek further treatment, the man's lawyer said Sunday.

"This morning, Vladimir Kara-Murza flew abroad with his wife Evgenia Kara-Murza, accompanied by physician to undergo a rehabilitation course after repeated severe poisoning (a few days earlier he had been in a critical state of coma)," reads a Facebook statement posted by Kara-Murza's lawyer, Vadim Prokhorov

Kara-Murza was released from a Moscow hospital, said Prokhorov, who did not reveal his client's destination.

"The diagnosis in the discharge summary is the same -- 'toxic effects of unknown substances,'" Prokhorov said.

The lawyer added that Kara-Murza plans to continue to pursue "the restoration of democracy in Russia."

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