The experts – who included lead designers Sergei Rizhov, Gennadi Benyok, Nicolai Tronov and Russia’s top nuclear technological experts, Andrei Tropinov – worked at Bushehr after the contract for the plant’s construction passed from the German Siemens company to Russian hands.

The five were employed at the Hydropress factory, a member of Russia’s state nuclear corporation, and one of the main companies to contracted for the Bushehr construction.

The sources said that the death of the scientists is a great blow to the Russian nuclear industry…

According to the sources, although Iranian nuclear scientists have in the past been involved in unexplained accidents and plane crashes, there is no official suspicion of foul play.