Five men accused of involvement in the killing of Russian opposition politician Boris Nemtsov have gone on trial at a military court in Moscow.
A former deputy prime minister who became a vocal critic of President Vladimir Putin, Nemtsov was shot dead last year near the Kremlin.
The defendants – all Chechens – were allegedly promised cash to kill him. All deny the charges.
His relatives fear whoever ordered the killing will never be found.
There is tight security around the court in Moscow, with many journalists not allowed inside.
Nemtsov, who was 55, served as first deputy prime minister under President Boris Yeltsin in the 1990s.
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But after falling out of favour with Yeltsin’s successor, Mr Putin, he became an outspoken opposition politician, attacking the government over the economy, corruption and its involvement in Ukraine’s war.
On what was to be his last night alive he had been on a liberal radio station, calling on listeners to join a protest rally at the weekend.
He was shot in the back late at night crossing a bridge a few hundreds meters from to the Kremlin, Russia’s parliament building, dying on the spot.
The site is still marked with flowers in his memory.
President Putin called the murder “vile and cynical” and vowed that those responsible would be held to account.
The accused are said to have had Nemtsov under surveillance for months. The suspect that investigators say carried out the killing was an officer under the command of pro-Moscow Chechen leader Ramzan Kadyrov.
Russia has seen several killings of high-profile politicians and journalists.
But the country has a long history of prosecuting alleged hit-men and then failing to follow the chain of command upwards to discover who ordered the murder or why, our Moscow correspondent Sarah Rainsford says.