One person was killed in an accident at a uranium enrichment plant in Russia's Urals region on Friday, RIA news agency said, but the factory said radiation levels at the site and surrounding area were normal.
The factory said a "depressurisation" of a cylinder containing depleted uranium hexafluoride had occurred, without saying what had caused this to happen.
The website of the Urals Electrochemical Combine says it enriches uranium for use in nuclear power plants. Uranium hexafluoride is a gas that is part of that process.
Radiation levels on the premises and in the surrounding area are normal, the plant in the city of Novouralsk said.
"There is no danger to the residents of Novouralsk and the plant personnel," it said in a statement.
