Russian secrecy over deadly nuclear accident fuels speculation

Russia's top nuclear official promised on Monday to succeed in developing new weapons as he paid tribute to five scientists killed in what U.S. experts suspect was the botched test of a new missile vaunted by President Vladimir Putin.

The five scientists were buried in the closed city of Sarov on Monday. They died last Thursday in what state nuclear agency Rosatom has said was an accident during a rocket test on a sea platform off northern Russia.

The defence ministry initially said background radiation had remained normal, but a spike in radiation levels recorded in a nearby city prompted U.S.-based nuclear experts to suspect the failed test involved a nuclear-powered cruise missile.

Greenpeace has said the incident caused a 20-fold increase in radiation in the city of Severodvinsk.

The experts said they suspected the radiation release resulted from a mishap during the testing of the Burevestnik nuclear-powered cruise missile, one of an array of new strategic weapons touted by Putin last year. Tensions between Moscow and Washington over arms control have been exacerbated by the demise this month of a landmark nuclear treaty.

The Kremlin has not commented on the accident.

At memorial events in Sarov that included a gun salute, Rosatom head Alexei Likhachev praised the deceased nuclear experts as the "pride of the country" and the "pride of the atomic sector."

"The best tribute to them will be our continued work on new models of weapons, which will definitely be carried out to the end," Likhachev was quoted as saying by RIA news agency.

In a video interview published late on Sunday, Russian officials at the nuclear research institute where the scientists had worked said the accident had caused a two-fold rise in radiation levels that had only lasted an hour.

Vyacheslav Solovyev, one of the officials at the institute in Sarov, did not spell out exactly what the nuclear experts had been working on, but said the institute worked on nuclear-powered energy sources.

He said its work served both civilian and military ends.

"One of the lines [of research and development] is the creation of sources of thermal or electric energy using radioactive materials, including fissile materials and radioisotope materials," he said.

"These developments are also actually happening in many countries. The Americans last year ... also tested a small-scale reactor.... Our centre also continues to work in this direction."

Valentin Kostyukov, head of the nuclear centre, which is part of state nuclear agency Rosatom, said a year of careful work had been carried out ahead of the test anda state commission was investigating what went wrong.

Elevated radiation fears

The nuclear experts battled to control the situation, but were unable to prevent the accident, Kostyukov said. He called them "national heroes" and said the institute had asked for them to be given posthumous state awards.

"These people were the elite of the Russian Federal Nuclear Centre and have tested under some of the most incredibly difficult conditions."

Rosatom said on Saturday the rocket test was carried out on a sea platform and a rocket's fuel had caught fire after the test, causing it to detonate, Russia's RIA news agency reported.

Sarov's city administration announced two days of mourning, saying the experts died while "performing a task of national importance," RIA reported.

Rosatom named the five as Alexei Vyushin, Evgeny Koratayev, Vyacheslav Lipshev, Sergei Pichugin and Vladislav Yanovsky.

Though the Defence Ministry initially said no change in radiation was detected after Thursday's explosion, local officials in the nearby city of Severodvinsk said radiation had briefly spiked, without saying how high.

Anxious local residents stocked up on iodine, used to reduce the effects of radiation exposure.

Moscow has a history of secrecy over major accidents, most notably after the1986 explosion at the Chornobyl nuclear power plant in the then-Soviet republic of Ukraine.