Russian police have named a Chechen man as the alleged mastermind behind the high-profile murder of opposition leader Boris Nemtsov, but the dead politician's supporters say he is only a low-level figure and that a cover-up is underway.
Nemtsov, one of President Vladimir Putin's most vocal critics, was shot dead on February 27 as he walked across a bridge near the Kremlin.
Aged 55, he had been working on a report examining the Russian military's role in the Ukraine crisis. His killing sent a chill through Russian opposition circles.
Police investigators said on Tuesday they planned to charge five men with his contract killing including the suspected trigger man, Zaur Dadayev, a former soldier in Chechnya, who initially confessed to the murder before recanting, saying he had been put under pressure.
Police for the first time also named the alleged mastermind, Ruslan Mukhudinov, a former officer in Chechnya's interior ministry.
Police had previously spoken of him as helping organise the crime, but on Tuesday described him as the person who had actually ordered the hit.
His lawyer says there is no solid evidence against him.
"He has been an international fugitive since November 2015," Vladimir Markin, a spokesman for Russia's Investigative Committee, said of Mukhudinov. "His arrest and his reckoning with the criminal charges against him is only a matter of time."
Vadim Prokhorov, a lawyer for the Nemtsov family, said the idea that Mukhudinov was the mastermind was "complete nonsense" and looked like a bad joke.
"That he is one of the low-level organisers is obvious," said Prokhorov. "But the masterminds are highly-placed people."
Zhanna Nemtsova, the dead politician's daughter, said she was disappointed with the development. She has previously said she wants Ramzan Kadyrov, the Kremlin-backed head of Chechnya, to be questioned about the case.
"There is no justice in Russia," Nemtsova told Reuters on Tuesday. "It is clear the Russian authorities have no desire to solve the case."
Ilya Yashin, a political ally of the late Nemtsov, said a cover-up was underway.
"If investigators did their work seriously and were not shielding the criminals, Kadyrov and his entourage would have been questioned long ago," said Yashin, saying he deemed it an "open question" whether the Chechen leader was involved.