The shut down happened at 09:32 Moscow time, reports the information centre at Kola nuclear power plant (Kola NPP).
The radiation background at the nuclear power plant and its surrounding areas are within normal background according to the on-line map of radiation detectors on the Kola Peninsula.
The three other reactors at Kola nuclear power plant are operating as normal.
UPDATE, December 7: The reactor was restarted again at 00:49 on December 7 after the faulty control cable of a transformer was replaced, reports Kola NPP in a press-release.
