Russian prosecutors on Thursday asked for a 15-year sentence in the treason trial of a Russian-American woman, who has pleaded guilty, Russian news agencies reported.

Ksenia Khavana, whom Russian authorities identify by her maiden name of Karelina, was arrested in Yekaterinburg in February, accused of collecting money for Ukraine’s military.

She pleaded guilty in the closed trial on Wednesday, news reports said, and the Interfax news agency on Thursday quoted her lawyer Mikhail Mushalov as saying prosecutors called for 15 years in prison. The sentencing is expected on Aug. 15, Mushalov was quoted as saying.

Khavana reportedly obtained U.S. citizenship after marrying an American and moving to Los Angeles. She had returned to Russia to visit her family.

The rights group The First Department said the charges stem from a $51 donation to a U.S. charity that helps Ukraine. Russia’s Federal Security Service claims she “proactively collected money in the interests of one of the Ukrainian organizations, which was subsequently used to purchase tactical medical supplies, equipment, weapons, and ammunition for the Ukrainian armed forces.”

Since sending troops into Ukraine in February 2022, Russia has sharply cracked down on dissent and has passed laws that criminalize criticism of the operation in Ukraine and remarks considered to discredit the Russian military. Concern has risen since then that Russia could be targeting U.S. nationals for arrest.

In the largest Russia-West prisoner exchange since the end of the Cold War, Russia last week released Wall Street Journal reporter Evan Gershkovich and American corporate security executive Paul Whelan, both of whom were imprisoned on espionage convictions, and U.S.-Russian dual national Alsu Kurmasheva, a Radio Liberty/Radio Free Europe journalist sentenced to 6 1/2 years for spreading “false information” about the Russian military.

Russia also released several prominent opposition figures who were imprisoned for criticizing the Ukraine military operation.