A Russian court on Thursday once again extended the detention of U.S.-Russian journalist Alsu Kurmasheva.
Kurmasheva, a Radio Free Europe/Radio Liberty (RFE/RL) journalist, was arrested last year for failing to register as a "foreign agent."
Her employer says she has also been charged with spreading "false information," which carries a potential jail term of up to 15 years.
At Thursday's closed-door hearing, Kurmasheva's lawyers had asked that she be released from house arrest, pending trial.
A court in the city of Kazan said it had ruled to keep her in pre-trial detention until April 5.
"Russian authorities are conducting a deplorable criminal campaign against the wrongfully detained Alsu Kurmasheva," RFE/RL President Stephen Capus said in a statement.
He said Kurmasheva had been "imprisoned and treated unjustly simply because she is an American journalist."
Kurmasheva, who before her arrest lived in Prague with her husband and two children, had her U.S. and Russian passports confiscated in June after traveling to Russia for a family emergency.
In October, she was arrested for failing to register as a "foreign agent."
Kurmasheva was subsequently accused of spreading "false information" about Russia's war in Ukraine, according to RFE/RL.
Her lawyers and family have denied the charges and called for her immediate release.
Kurmasheva is the second U.S. journalist to be arrested in Russia over the past year.
Wall Street Journal reporter Evan Gershkovich is also being held in pre-trial detention in Moscow on espionage charges that carry a maximum sentence of 20 years in prison.
He too has denied the charges.
RFE/RL is pushing for the United States to designate Kurmasheva "wrongfully detained," which would grant extra diplomatic support from Washington to secure her release.
The U.S. State Department said last year that Kurmasheva's arrest "appears to be another case of the Russian government harassing U.S. citizens."
