A State Department official says the United States has concluded that a mysterious explosion that occurred at a Russian naval test range in the White Sea in August occurred amid an operation to recover a nuclear-powered missile that had apparently crashed during a test.
The August 8 incident sent analysts from Washington to Brussels to Oslo scrambling to figure out what was going on, and was followed by contradictory statements from local and federal government officials in Russia about the nature of the explosion and the danger it posed to local residents.
“The United States has determined that the explosion…was the result of a nuclear reaction that occurred during the recovery of a Russian nuclear-powered cruise missile,” U.S. Deputy Assistant Secretary of State Thomas G. DiNanno told a United Nations committee on October 10, according to prepared remarks.
That conclusion bolsters earlier RFE/RL reporting about the blast at the Nyonoksa test range, which panicked and angered residents.
“The missile remained on the bed of the White Sea since its failed test early last year, in close proximity to a major population center," DiNanno said.
It wasn’t immediately clear why the United States decided to publicly confirm its intelligence conclusions about the August 8 explosion now.
The blast sent a plume of radiation wafting over the White Sea shipbuilding port of Severodvinsk, sending spooked residents rushing to buy up iodine drops from local pharmacies. Iodine is often used as a first resort to protect the thyroid gland from being irradiated in the event of a nuclear incident.
Severodvnisk is just 30 kilometers east of Nyonoksa and is home to a sizable naval presence as well as a shipbuilding factory where nuclear-powered submarines for the Russian fleet are built.
The day the blast happened, the Russian Defense Ministry confirmed a fatal incident at the range, which has been used for decades by the Soviet and Russian navies for weapons testing. The ministry said that two people had been killed but gave no other details.
Two days later, the state-run atomic energy agency Rosatom revealed that five of its employees had been killed while they were conducting "technical-engineering oversight" of a test of "radioactive isotope fuel for a liquid-fueled rocket engine."
On August 11, managers at the state research institute where the engineers were employed revealed in a video interview that the researchers had been investigating, among other things, "the creation of small-scale sources of energy using radioactive fissile materials."
The institute where the men worked is Russia's premier facility for military nuclear research, known by its acronym VNIIEF and located in the closed city of Sarov.
Meanwhile, monitoring stations in Severodvinsk reported a brief spike in radiation levels in the hours after the explosion but emphasized that there was no danger to public health.
On August 26, Russia's federal weather agency said its sensors had detected several radioactive isotopes, including those that independent experts said were associated with a nuclear reaction, or a "fissile event."
Taken together, the reporting added to speculation that the explosion was linked to a nuclear-powered missile that President Vladimir Putin had boasted was under development last year.
That missile, known in Russian as the Burevestnik and under NATO standards as Skyfall, had reportedly suffered several failures during testing, and there has been at least one reported previous attempt to recover a missile lost at sea.
Putin himself said the explosion occurred during a test of a new weapons system, but he gave no details.
Under Putin, Russia has moved to upgrade its nuclear arsenal and its overall weapons systems.
In the weeks after the explosion, residents of the village of Nyonoksa were openly critical of authorities for a lack of information about what had occurred. Their anger was deepened by the presence of debris, apparently from the test, that had either washed up on the shore or was deliberately left there.
Some of the debris was visibly damaged, and matched up with the satellite imagery that added to evidence of some sort of weapons malfunction.
Asked last month for comment on the criticism leveled by Nyonoksa residents about the lack of information from Rosatom, an agency spokesperson told RFE/RL: "Rosatom is not in a position to comment on classified defense contracts and military tests.
DiNanno’s comments came in remarks during a meeting of the United Nations First Committee in New York.
That committee is one of six primary committees at the world body, and deals specificially with disarmament and arms-control issues.
An e-mail sent to the U.S. State Department on October 12 was not immediately answered.