Alexei Navalny’s team believe Vladimir Putin ordered activist’s death

Prison authorities in Russia have told the mother of Alexei Navalny her son died of “sudden death syndrome”, according to an ally of the dead activist.

Navalny ally Ivan Zhdanov posted the update on X, formerly Twitter, as Navalny's family await the return of his body.

Navalny's team has claimed he was murdered and accused Russian authorities of withholding his body to “cover traces”.

Confirmation of Navalny’s death was communicated by his allies on Saturday. He died at 2:17pm local time on 16 February, according to a document given to Navalny’s mother, Lyudmila.

In comments to the BBC, spokesperson Kira Yarmysh, said Navalny's team believes Vladimir Putin ordered the death of the activist.

Navalny’s death at the Arctic penal colony where he was being detained was announced on Friday by the prison authorities. He was arguably the Russian president's most famous critic and his supporters say he was jailed for political reasons.

Yarmysh said: “We know for sure that it wasn’t just a death, it was a murder. They are trying to cover traces, this is why they are not giving the body to his family and this is why they are just hiding him from them.”

She said she does not know where the body is and when it will be given to Navalny's family.

Yarmysh explained that according to Russian laws, the body of an inmate should be given to relatives within two days after the death.

The Russian Foreign Ministry said it rejected “biased and unrealistic” assessments from the UK about the cause of Navalny's death.

UK Foreign Minister David Cameron has said there will be consequences for Russia over Navalny’s death.

Meanwhile, across Russia, the authorities have been scooping up flowers and tributes left to Navalny, to suppress any public sign of support for Putin’s biggest rival.

In Moscow, a video showed what looked like men in dark tops, with their hoods raised, moving in to clear the many tributes laid at the Solovetsky Stone, a monument to the victims of political repression in Stalin’s time.

The carnations and roses had been piled high on and around the stone – and at another monument in St Petersburg – as a stream of Navalny’s supporters turned out to remember him. Some left photos of the politician, and small notes of protest and defiance.

The video from Moscow showed police blocking access to the site, while the shrine was removed.

Men in civilian clothing, again with their hoods up, also removed tributes left on the bridge near the Kremlin where the opposition politician Boris Nemtsov was murdered in February 2015. Again, police stood by and watched.

Malta’s Foreign Minister Ian Borg told MaltaToday Navalny’s sudden death is of “serious concern”, adding that Malta mourned the loss of a “courageous leader”.

“Malta calls for an independent and transparent investigation into the circumstances surrounding his death. Our thoughts are with his family and all those who stand for the ideals of democracy and fundamental freedoms with such bravery and conviction,” Borg said.