Russian citizen Maria Butina, currently in custody in the United States, is locked in a solitary confinement cell for 22 hours a day and is prohibited from open air walks, her father Valery Butin said in an interview with Russia’s Izvestia daily.

"She is allowed only 60 minutes per day to stretch out and do some sports," the daily quoted Valery Butin as saying. "On the whole, her segregation regime implies 22 hours presence in a solitary confinement cell each day. She is not allowed for open air walks."

He added that his daughter is permitted to leave her prison cell only at night and is also allowed to make a telephone call to her relatives at one o’clock in the morning local time. Valery Butin said his daughter was subjected to a psychological pressure to force her into making a confession of an alleged crime.

Maria Butina, 29, was arrested in Washington on July 15, on the eve of the Helsinki summit between Russian President Vladimir Putin and his US counterpart Donald Trump. The Russian gun rights activist is facing charges of conspiracy for conducting activities in the interests of a foreign state. Investigators claim that she was engaged in these activities without registering as a foreign agent at the US Department of Justice.

The FBI said Butina arrived in the United States in August 2016 on a student entry visa and took up studies at the American University. She received the master’s degree in international relations in May 2018, according to her lawyer.

Butina is a member of the board of the Russian public associations ‘The Right to Guns’. In this capacity, she attended the National Prayer Breakfast in Washington in February 2017 where President Donald Trump took part.