Doctor who treated Navalny missing

A Siberian doctor who treated Kremlin critic Alexei Navalny after he collapsed on a flight in Russia last year has gone missing, police said on Sunday.

Police in the Omsk region, about 2,200 kilometres east of Moscow, said physician Alexander Murakhovsky had left a hunting base in a forest on an all-terrain vehicle on Friday and had not been seen since.

It said that emergency services, drones, a helicopter and volunteers on the ground had joined the search effort.

Murakhovsky was the head doctor at the hospital in the Siberian city of Omsk that treated Navalny, President Vladimir Putin's most prominent critic. Murakhovsky was subsequently promoted to the post of regional health minister.

The Kremlin has repeatedly rejected any suggestion that Russian authorities tried to kill Navalny.