French police find weapons cache in home of Champs Elysees attacker

A judicial source said investigators were compiling an inventory of the arms and equipment found in the 31-year-old's home. The man, who died in the attack, was also carrying in his car an assault rifle, two pistols, ammunition and two large gas canisters when he rammed a police convoy on Monday.

Prime Minister Edouard Philippe said the individual first received a permit to possess a gun before he was flagged to intelligence agencies as a potential militant threat. At the time, there was no reason to deny him the permit, Philippe said.

Philippe said it was "quite possible" the licence was active at the time the attacker was on a security watch list. Three sources close to the investigation confirmed it was.

"Nobody can be happy, and certainly not me, that someone who has been flagged to security agencies can continue to benefit from such an authorisation," Philippe told BFM TV.

The man was placed on France's so called 'Fiche S' watch list after he was found to belong to a radical Islamist movement, two police sources said.

Individuals on the list are placed under surveillance though the intensity of that surveillance varies depending on the perceived threat the individual poses.