This story is from 2016 and unrelated to the fire at Notre-Dame on April 15 2019

Gas tanks and documents in Arabic were found in an unmarked car next to Notre Dame cathedral, sparking fresh terror fears and at least four arrests, according to French reports.

A couple known to intelligence services as being "favourable to the ideas of Isil" were arrested on Tuesday night on their way to Spain, after an anti-terror investigation was launched following the discovery of the suspicious vehicle containing up to seven cylinders on Sunday yards from the cathedral - one of Paris's most visited landmarks.

A second couple was detained overnight on Wednesday.

Documents in Arabic were reportedly found inside the car outside the cathedral and were "in the process of being translated".

The car, a Peugeot 607 with no number plates, contained no explosives or detonators, according to French reports. "They were not linked to any kind of fuse," one source close to the investigation told l'Express. Its warning lights were on.

According to BFM TV, one empty canister was found in the back of the car and six full ones in the boot. The type of gas they contained was not specified.