Robert Gilman, from Massachusetts, was freed "from detention for humanitarian reasons" and flying on a US plane to Washington, DC, on Tuesday, according to Kirill Dmitriev, special envoy for Russian President Vladimir Putin.
Massachusetts Senator Ed Markey posted on social media that Gilman had been "essentially catatonic" and battling a "severe case of pneumonia" before he was released.
Gilman was 28 when he was arrested for kicking a police officer while drunk aboard a train to Moscow.
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