The Los Angeles resident pleaded guilty at her closed trial in the Urals city of Yekaterinburg, where her case was heard by the same court that convicted Wall Street Journal reporter Evan Gershkovich of espionage in July.
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The court said investigators found that Karelina had, on February 24, 2022 – the first day of Russia's invasion of Ukraine – "transferred funds in the interests of a Ukrainian organisation, which were subsequently used for the purchase of tactical medicine items, equipment, means of defeat and ammunition by the Armed Forces of Ukraine".
Her supporters say she had donated $51.80 (about R930) to Razom for Ukraine, a New York-based charity that provides humanitarian aid to children and elderly people in Ukraine. The charity has denied it provides any military support to Kyiv.
Karelina appeared in court on Thursday in a white sweatshirt and blue jeans, sitting calmly in a glass courtroom cage.
The 33-year-old was not included in a major prisoner swap between Russia and the West last week that freed Gershkovich, but her lawyer Mikhail Mushailov has said she hoped to be included in a future exchange.
Karelina was born in Russia and emigrated to the US in 2012, receiving American citizenship in 2021. She was arrested by the FSB security service after flying to Russia to visit her family in Yekaterinburg at the start of the year. Reuters