A fire caused an explosion at EDF's Flamanville nuclear power plant in northern France on Thursday, leading the utility to take a reactor offline, but there was no associated nuclear risk, EDF and a local government official said on Thursday.
State-owned EDF said in a statement a fire in a machine room caused the explosion in a "non-nuclear" part of the power station.
It added that the fire had been brought under control by its team there and that reactor number 1 had been disconnected from the grid.
It said there were no injuries but five people had been affected by fumes.
The Flamanville 1 and 2 reactors, which each have a electricity generating capacity of 1,300 megawatts, were built in the 1980s. A new reactor is being built at the site but the explosion was not there, a spokeswoman said.
The nuclear safety authority ASN said it had no information and could not immediately comment.