Paris was put on lockdown on Thursday as police set up roadblocks on each of the city's main access roads, after a range of unverified and somewhat confused reports suggesting that two of the gunmen behind the Charlie Hebdo magazine massacre were attempting to head back to the capital.
Heavily armed police and armored vehicles were stationed on checkpoints on the highways and elite police units were deployed in the area north east of Paris where the attack suspects were spotted.
The extra security was deployed after the two suspects were spotted at a gas station in the north-eastern department of Aisne, apparently driving off in the direction of Paris. However, some reports suggested they had robbed the station in Villiers-Cotterets, 43 miles from the capital, while others said they had merely been seen there.
The BBC cited the manager as saying the men fitted the description of the brothers Said and Cherif Kouachi, who have been named as the suspected Charlie Hebdo shooters, and that they were heavily armed with Kalashnikovs and rocket-propelled grenade launchers. Reuters reported that they had been seen at the station in a Renault Clio car armed and wearing cagoules, according to two police sources.
The capital has been on high alert since the Charlie Hebdo attack and 800 troops were deployed around the city and surrounding regions on Wednesday night and Thursday, including in front of landmarks and tourist spots. Armed police have also been stationed around schools, landmarks and places of worship.
The French Interior Ministry said in a statement that more than 88,000 security personnel across the country were engaged in the search for the shooters, including 40,000 members of the national police force, 32,000 local police, 7,000 border officers and 1,150 troops.
Yet amid conflicting reports and official silence it was unclear on Thursday afternoon if security forces were managing to close the net on the suspects. Counter-terrorism police fanned out in small villages and a forest close to the gas station, television footage showing the incongruous spectacle of armored vehicles and heavily armed officers going house to house in quiet country lanes.
There was reportedly a substantial security force presence in the villages of Corcy - where some, unverified accounts suggested the men may have abandoned their car - Crepy-en-Valois, and Abbaye de Longpont.
Bruno Fortier, the mayor of Crepy-en-Valois, told Reuters that he was unable to confirm reports that the men may have sought refuge in a house in the area.
"It's an incessant waltz of police cars and trucks," he said, adding that helicopters were circling overhead.
What is in no doubt, however, is that the attack, and the ensuing manhunt, has further frayed nerves across a continent already in a state of heightened terror alert. Spain joined France in raising its threat level immediately after Wednesday's attacks. The UK is to tighten border security, Prime Minister David Cameron's office said after a meeting of Cobra, the British government's crisis response committee, adding that the risk of a terrorist attack in the country is still "severe."
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