Russia's leading rocket specialist Pavel Kamnev has died.
Vladimir Putin has been rocked by the death of another key Russian defence official
The scientist responsible for developing the deadly Kailbr missiles deployed by Vladimir Putin in the Ukraine war has passed away at the age of 85.
Pamnev is the fourth key defence official to pass away in less than three weeks.
He was the scientific director of the Almaz-Antey Aerospace Defence Concern and was responsible for more than 20 weapons inventions and co-authored over 300 scientific and technical reports.
An Almaz-Antey spokesperson said: "He took an active part in the development of many missiles."
A video shows him being made a Hero of Labour by Putin in 2016 as he lauded the despot for the "highest appreciation" of his missile-making work "so that our country can live in peace and security".
Pamnev's death is the latest to rock Moscow after the passing of the Angara rockets inventor Vladimir Nesterov last week.
He was regarded as the brains behind Putin's dreams of Russia exploring the moon and outer space.
Nesterov's passing followed the "sudden death" of Alexander Buzakov - the director general of Admiralty Shipyards who was in charge of building new submarines armed with the Kalibr missiles.
Meanwhile, General Alexei Maslov, the former commander of the Russian ground forces with close ties to Ukraine, died "suddenly" last month after Putin abruptly cancelled a trip to the tank enterprise where he had worked as an international sales ambassador.