The wreckage of Tu-134 plane, belonging to the RusAir airline, is seen on a highway near the city of Petrozavodsk Tuesday, June 21, 2011.
The five Russian scientists were among 44 killed earlier this week; no official investigation of foul play has been opened, though Iranian nuclear experts have in the past been involved in similar accidents.
The five nuclear experts killed in a plane crash in northern Russia earlier this week had assisted in the design of an Iranian atomic facility, security sources in Russia said on Thursday.
The five Russian experts were among the 44 passengers killed when the Tupolev-134 plane broke up and caught fire on landing outside the northern city of Petrozavodsk on Monday.
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.
The experts were tasked with completing construction of the plant and for ensuring that it would be able to survive an earthquake.
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. Investigators are investigating human error and technical malfunction as the causes of the crash.