Alexei Navalny to be buried in Moscow amid uncertainty, tight security

Russian opposition politician Alexei Navalny will be buried in Moscow on Friday amid tight security and fears of a police crackdown two weeks after he suddenly died at the age of 47 in an Arctic penal colony.

A religious service for Navalny is due to be held at 1400 local time in the Church of the Icon of the Mother of God in the Moscow district of Maryino where Navalny used to live.

He is then scheduled to be buried at the Borisovskoye cemetery, around 2.5 km away on the other side of the Moskva River two hours later.

Navalny's allies, who are outside Russia and have been designated as US-backed extremists by the authorities, have called on people who want to honour his memory but cannot attend his funeral service to instead go to certain landmarks in their own towns on Friday at 7:00 pm local time.

Judging from previous gatherings of Navalny supporters, a heavy police presence is likely and the authorities will break up anything they deem to resemble a political demonstration under protest laws.

There was heavy security at the church on Friday morning which was surrounded by metal crash barriers with dozens of police vehicles parked nearby.

Navalny's wife Yulia, with whom he had two children, has said she is unsure whether the funeral itself will pass off peacefully or whether police will arrest attendees. She is outside Russia.

Navalny's mother Lyudmila, 69, is expected to attend his funeral. It is unclear who else will be allowed into the church for the service.

Rights group have advised those who want to attend to take their passports and small bottles of water with them and told them to write down the details of lawyers who can help them in case they are detained and the mobile signal in the area is cut.

In the run-up to his funeral, his allies accused the authorities of blocking their plans to hold a bigger civil memorial service and said unknown individuals had even managed to thwart their attempts to hire a hearse to transport him to his own funeral.

The Kremlin has said it has nothing to do with Navalny's funeral arrangements.

Navalny, a former lawyer, mounted the most determined political challenge against Putin since the Russian leader came to power at the end of 1999, organising street protests and publishing high-profile investigations into the alleged corruption of some in the ruling elite.

Navalny's allies have accused President Vladimir Putin of having him murdered because the Russian leader could allegedly not tolerate the thought of Navalny being freed in a potential prisoner swap.

They have not published proof to back up that accusation, but have promised to set out how he was murdered and by whom.

The Kremlin has denied state involvement in his death and has said it is unaware of any agreement to free Navalny. His death certificate - according to allies - said he died of natural causes.