The man, a 24-year-old Algerian national and information technology student who has not been named, was arrested in southeast Paris. A car was also seized along with handguns, other weapons and bulletproof vests, Interior Minister Bernard Cazeneuve said.
Despite a huge anti-terror operation after Islamist militants killed 17 people in January in attacks on the offices of the Charlie Hebdo satirical weekly and a Jewish food shop, the man was only arrested after alerting police of his wheareabouts.
Um, France didn't foil it so much as they got lucky the terrorist shot himself. https://t.co/SCgnicBuRU
— Amy Curtis (@moderncomments) April 22, 2015
He was arrested after calling emergency services to treat a wound, the interior ministry source said. When they arrived, they saw the injury was a gunshot wound and notified police. A blood trail led to a car which contained the weapons.
An Interior Ministry source said the man, also suspected of being involved in the murder of a 32-year-old woman found dead in her car on Sunday, was an Algerian national.
"Detailed documents that were also found established beyond doubt that the individual was planning an imminent attack, probably on one or two churches," Cazeneuve said. Police suspect the 24-year-old accidentally shot himself, the source said.
You know I always say wannabe terrorist martyrs should start by shooting themselves… http://t.co/ymy5h1KbgD
— Zeddonymous (@ZeddRebel) April 22, 2015
The intelligence blunder was compounded when it was revealed that the man had previously come to the attention of the French authorities as possibly wanting to go to Syria. Police had made checks on him in 2014 and 2015 without finding anything that would warrant further investigation.
According to RTL radio, police also discovered flashing blue lights of the type that fix magnetically to police car roofs, as well as orange "Police" armbands that are used by French plainclothes officers.
Cazeneuve said the man, who has not been named, was known to intelligence services for wanting to fight with jihadists in Syria. France has heightened surveillance by police and intelligence agencies since the January attacks, with 10,000 soldiers patrolling sensitive sites across France.
"France, like other European countries, is facing a terror threat of an unprecedented nature and amplitude," Cazeneuve told RTL Radio. "We are maintaining total and constant vigilance."
