Sept. 25 (UPI) -- Crews have begun to clean up the site of a nuclear accident in Russia this summer that killed seven people and caused a brief release of radiation into the atmosphere.
Helicopters, soil excavators and crews in hazmat suits have been working at the site in Nenoska, in northwest Russia, since last weekend. U.S. satellite photos indicate the presence of a nuclear-powered cruise missile at the bottom of the White Sea at the time of the Aug. 8 explosion.
The missile is believed to be the SSC-X-9 Skyfall -- an experimental, nuclear-powered missile with unlimited range -- and authorities believe Russia was trying to salvage the weapon when the accident occurred.
A video broadcast by a Russian news agency showed an excavating vehicle depositing scrap metal into a shipping container, which was then removed by helicopter. The footage shows crews aboard barges holding the containers wearing protective equipment.
Russian President Vladimir Putin has said the accident occurred while testing a new weapons systems.
Background radiation levels climbed as much as 16 times higher than normal after the accident. Four Russian monitoring stations offered no data in the days after the explosion, and local doctors said they weren't advised of any patients with radiation poisoning.
The Nenoska explosion was the second for Russia in just three days. A blast at a Russian military depot near Achinsk on Aug. 5 prompted thousands to evacuate in Kamenka.