French police have arrested five people after the discovery of an explosive device outside a residential building in Paris.
Authorities believe the device, which was discovered on Friday, was part of a failed bomb plot in the city's 16th arrondisement, a wealthy neighbourhood in the west of the capital home to Paris Saint-Germain's (PSG) stadium.
One of those arrested was “radicalised”, France's interior minister said, a likely reference to Islamist terrorism.
Gerard Collomb, speaking on French radio, said the discovery of the device highlighted that the threat against France remains "extremely big".
“(Police) services are investigating,” he said. “What I can tell you is that among the people who were arrested, one was... radicalised.”
More than 230 people have been killed in attacks by Islamist militants over the past three years. Isis, whose bases in Syria and Iraq are being bombed by French war planes, has urged followers to attack France.
Soldiers shot a man dead on Sunday after he killed two young women with a knife at a train station in the southern French port city of Marseille.
A judicial source said the explosive device found late last Friday night was made of four gas canisters and covered in petrol.
The discovery came hours before PSG played at their Parc des Princes stadium, thrashing Bordeaux 6-2. Police have made no indication that the apparent failed bomb plot was targeting the club.
“We've foiled numerous attacks since the start of the year that would have involved many deaths,” Mr Collomb said. “We are still in a state of war.”
Additional reporting agencies
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