A man with connections to Norwegian mass killer Anders Behring Breivik has been arrested in France after investigators decided he might stage a large "terrorist act".
Kristian Vikernes, who was convicted in 1994 for stabbing a man to death in Oslo, had in the past received a copy of a manifesto from Breivik, who killed 77 people in 2011.
Mr Vikernes, 40, a musician in Norway, was arrested with his French wife Marie Chachet after she recently bought four rifles, according to French Interior Minister Manuel Valls.
"Having received the manifesto before (Breivik) committed his crimes and having been sentenced in Norway in the past for murder, this individual, who was close to a neo-Nazi movement, was likely to prepare a large terrorist act," Mr Valls said.
Officers were searching his home in Correze for weapons and explosives, according to police sources.
Breivik killed 77 people in a bombing in central Oslo and a shooting spree on a nearby island in July 2011.
He was imprisoned last year for a maximum term of 21 years.
Breivik sent a copy of his manifesto setting out his ideology to Mr Vikernes, an official at the Paris prosecutor's office said.
The 1,500-page document outlined his planned crusade against Muslims, who he said were taking over Europe and could only be defeated through a violent civil war.
Ms Chachet, 25, had a legal firearms permit when she bought the four rifles.
"The investigation will notably establish the conditions in which these (rifles) were acquired and their real objective," Mr Valls said.
On his website, Mr Vikernes discusses Breivik's manifesto, but he also criticises the murderer for killing innocent Norwegians.
Mr Vikernes was convicted in 1994 of stabbing a rival musician to death and burning down several churches.
He was released from jail in 2009 and moved to France with his wife and three children.