Five workers were killed in an accident during a missile test at a military site in northern Russia, the country’s state nuclear agency Rosatom has confirmed.
The agency refused to say whether there had been a release of radiation as a result of the accident on Thursday.
A further three staff members suffered injuries, including burns, and are receiving medical treatment in specialised facilities, the agency said.
Russian authorities had previously said two people were killed in the incident and that a nearby city had reported a rise in radiation levels when a liquid propellant rocket engine blew up at a testing site in the Arkhangelsk region.
The accident happened during the engineering and technical support of “isotope power sources” on a liquid propulsion system, Rosatom said in a statement.