A mysterious blast that took place in Russia’s Arkhangelsk region Thursday, which sent people in nearby areas scurrying to stock up on iodine due to fears that a nuclear leak is involved. Authorities have provided scant and sometimes contradicting information about the explosion, but here are some of the things we know so far about the this blast.

Drove Up Radiation Levels

The Guardian reported that the blast caused radiation levels to spike by up to 20 times the normal levels in neighboring cities.

The Russian defense ministry initially said it detected no changes in radiation after the explosion, but officials in the neighboring city of Severodvinsk said radiation levels spiked. The event even prompted local residents to stock up on iodine, which is known to reduce the effects of radiation exposure.

In a radio interview, Russian officials at the nuclear research institute said the accident caused a two-fold increase in radiation levels that lasted an hour.

Russia also closed a bay in the White Sea for a month, a move that drove speculation the water has been contaminated or a search operation is being conducted.

Pictured is a violent explosion Pixabay

Caused By Failure Of Nuclear-powered Cruise Missile

The defense ministry said the blast happened during the testing of a rocket engine. The country’s nuclear agency, Rosatom, on the other hand, said its employees were killed during testing of an “isotope power source in a liquid propulsion system."

David Cullen, the director of the Nuclear Information Service in the UK, however, said that independent nuclear experts think that the explosion was caused by the failure of an experimental nuclear-powered cruise missile known in Russia as the 9M730 Burevestnik and by Nato as the SSC-X-9 Skyfall.

The missile can use an onboard source of nuclear fuel to heat fast-moving air and fly for indefinite periods.

Experts on the country’s nuclear program reportedly spotted the nuclear fuel carrier ship Serebryanka near the site of the explosion.

“Our suspicion is that something went wrong during or after a Russian test of its nuclear-powered cruise missile,” said U.S. arms control specialist Jeffrey Lewis, from Middlebury Institute of International Studies.

Deadly Accident

The explosion killed at least five people who reportedly worked for the nuclear center based at the closed city of Sarov. The center is a part of the country’s state nuclear agency Rosatom. Sarov’s administration said the experts died while performing a task of national importance.

Alexei Vyushin, Evgeny Koratayev, Vyacheslav Lipshev, Sergei Pichugin and Vladislav Yanovsky have been hailed as national heroes and given posthumous awards.