"The court has rejected the appeal. The [city] court's decision has been left unchanged," Domansky said.
Vyshinsky was detained in Kiev on May 15 on suspicion of supporting the breakaway republics of Donbass and on treason charges. The maximum penalty for such offense is 15 years of imprisonment.
READ MORE: Russia Demands Ukraine to Stop Legal Arbitrariness Toward Vyshinsky — Moscow
Russian President Vladimir Putin has said that Vyshinsky's arrest was politically motivated, adding that the incident demonstrated an unprecedented and unacceptable policy of Ukrainian authorities targeting journalists who were just doing their jobs.
On December 27, the Kherson city court extended Vyshinsky's detention until January 27. The defense asked the court to release Vyshinsky, with Domansky personally pledging for him.