Russia’s nuclear agency has said five of its employees were killed when a rocket engine exploded during a test at a far-northern military base.

Soon after Thursday’s explosion, the Defence Ministry said two people died and four were injured, including servicemen and civilian engineers.

It was not immediately clear if the five fatalities cited in a Saturday statement by Rosatom were in addition to the previously reported deaths.

The explosion occurred at a military shooting range in Nyonoksa in the north-western Arkhangelsk region.

Nyonoksa hosts a navy facility that serves as a base for testing intercontinental ballistic missiles intended for nuclear submarines.