This was reported by TASS with reference to the Federal Bureau of Prisons, which reports to the US Department of Justice.
Butinu was detained in the United States in July 2018 on suspicion of "working for Russia as an agent." She went to a deal with the investigation and pleaded guilty to conspiracy.
On April 26, 2019, the court sentenced Butin to 18 months in prison for "conspiring to work illegally for the Russian government."
The Russian embassy called the sentence Butina "blatant lawlessness."