In this photo taken on Monday, Aug. 5, 2019, a family watches explosions at a military ammunition depot near the city of Achinsk in eastern Siberia's Krasnoyarsk region, in Achinsk, Russia. Credit: Dmitry Dub | AP

Russian officials reported a brief spike in radiation levels after a blast during a missile test killed two people at a Barents Sea military facility near shipyards that produce nuclear submarines.

A “short-term increase in radiation” was detected in the port city of Severodvinsk at 11:50 a.m., according to a statement from the local administration. Radiation levels then declined to within a normal range as of 2 p.m., it said. The accident occurred in the town of Nyonoksa, about 25 miles from Severodvinsk, Interfax reported.

Radiation was at normal levels after the explosion, which also injured six, that occurred during the testing of a missile engine, a Russian Defense Ministry spokesman said. The area in Russia’s northern Arkhangelsk region is home to a weapons testing range for the navy.

The incident comes after a series of massive explosions earlier this week at a Siberian military depot killed one and injured 13, as well as forcing the evacuation of 16,500 people from their homes. Russia’s navy has suffered numerous high-profile accidents over the years. In July, 14 sailors died in a fire aboard a nuclear-powered submarine in the Barents Sea in an incident on which officials initially refused to comment.

Russia’s worst post-Soviet naval disaster also occurred in the Barents Sea, when 118 crew died on the Kursk nuclear submarine that sank after an explosion in August 2000.