Two leading Russian activists were detained in central Moscow while demonstrating to demand the release of the head of the human rights group Memorial's office in the North Caucasus region of Chechnya, Oyub Titiyev.
Memorial chairman Oleg Orlov, 65, and the head of the Civic Assistance Committee, Svetlana Gannushkina, 76, were detained on Manezh Square outside the Kremlin on July 9 while holding posters saying "Free Oyub Titiyev!"
Meanwhile, in a preliminary hearing, a court in Chechnya set a July 18 date for the start of Titiyev's trial on a drug-possession charge that he and colleagues contend was fabricated.
The Shali District court also extended Titiyev's pretrial detention until December 22, leaving him in jail and defying calls by rights groups and Western governments for his release.
The preliminary hearing had been postponed from July 3 after Titiyev's lawyers sought to move the trial to Moscow or another region, arguing that courts in Chechnya would be biased because senior officials there have essentially pronounced him guilty.
The top court in Chechnya, which is ruled by Kremlin-allied strongman Ramzan Kadyrov, rejected the request for a change of venue.
Titiyev has been in jail since his arrest in January, when police said they found marijuana in his car. Titiyev and colleagues at Memorial accuse the police of planting the drugs, and the case is widely seen by Russian and international rights activists as punishment for his work exposing rights abuses in Chechnya.
Titiyev, 60, could be sentenced to 10 years in prison if convicted, and acquittals are very rare in Russian courts. Rights groups and Western governments have called on Russia to release him and end what they call his politically motivated prosecution.
Human Rights Watch has called the charges "bogus" and said the case "seems to be part of an effort by Chechen authorities to shut Memorial out of the region."
With reporting by Interfax and Novaya Gazeta