Five people detained over the killing of Kremlin critic Boris Nemtsov have appeared in court in Moscow.
A judge ruled that all five should be held in custody and said one of them, Zaur Dadayev, had admitted his involvement in the killing when questioned by investigators.
He and another accused, Anzor Gubashev, have been charged in connection with the killing. Police have asked the court to issue formal arrest warrants for the three other suspects.
Boris Nemtsov was shot in the back on the night of 27 February as he was walking with his girlfriend within sight of the Kremlin. It was the most high-profile killing of an opposition figure in the 15 years that President Vladimir Putin has been in office.
Some associates of Mr Nemtsov, a 55-year-old former deputy prime minister who became a Putin critic, say the Kremlin stands to gain from his death. Russian officials deny involvement and Putin has condemned the killing.
Zaur Dadayev served for a decade in the "Sever" police battalion, part of the interior ministry in Chechnya, Russian news agencies reported.
The court hearings on Sunday were given extensive coverage on state-controlled media, and presented as proof the authorities are conducting a thorough investigation - not the cover-up some of Mr Nemtsov's friends say they anticipate.
But associates of Mr Nemtsov say they will not be satisfied unless prosecutors track down whoever orchestrated the killing, rather than just the people who pulled the trigger, Reuters reports.
There was no word from investigators on who the suspects were alleged to have been working for. The judge presiding over the hearings said investigators were still looking for others they believe were involved in the killing.
Russian media reports said most of those detained were from Chechnya or other parts of the North Caucasus, a poor and often violent area on Russia's southern flank.
Several other high-profile killings in Russia, including the 2006 shooting of journalist Anna Politkovskaya, have been attributed to gunmen from the North Caucasus, while those who ordered the crimes were never firmly identified.