French security forces yesterday fanned out in heavy armoured vehicles and helicopters in a hunt for two "armed and dangerous" brothers suspected of gunning down 12 people in a cold-blooded attack on a satirical weekly which lampooned Islam.
The mood was tense. Prime Minister Manuel Valls said he feared the two militants, Said Kouachi, 34, and Cherif Kouachi, 32, could strike again. A third suspect surrendered to police.
There were scattered, unconfirmed reports of sightings of the two men. One said two masked attackers carrying semi-automatic rifles had robbed a petrol station 70km north-east of Paris, prompting French police and anti-terrorism forces to deploy en masse.
Across France, hundreds of police officers and soldiers patrolled airports, schools and tourist sites, including the Eiffel Tower and the Louvre.
"We are confronting an exceptional risk that can lead, at any moment, to other instances of violence," Interior Minister Bernard Cazeneuve said, adding that seven people were being questioned about the shootings. The country has raised the terror alert status to its maximum level.
The bells of Notre Dame Cathedral in Paris tolled at midday as the stunned nation observed a minute's silence after experiencing the worst terrorist attack in more than 40 years on Wednesday.
Public transport came to a halt and people gathered outside the headquarters of the Charlie Hebdo magazine in pouring rain, holding signs that said: "Je Suis Charlie" (I am Charlie).
The mourning was spiked with tension after gunfire rang out for a second day in the capital. A gunman armed with an automatic rifle shot dead a policewoman and wounded a city employee just to the south of Paris.
There was an explosion at a kebab shop in eastern France. It was unclear if the two incidents were related to Wednesday's attack.
In what seemed to be retaliatory action, Muslim places of worship in two French towns were fired upon overnight. France's Muslim Council called on "all imams in all of France's mosques to condemn violence and terrorism wherever it comes from in the strongest possible way".
There were demonstrations of solidarity around the world. Tens of thousands of people rallied at public squares and French embassies in various cities.
In a sign of defiance, the magazine, which lost eight journalists in the attack, said it would publish as scheduled next Wednesday and print one million copies, instead of the usual 60,000.
"We are all suffering, with grief, with fear, but we will do it anyway because stupidity will not win," one of its staff, columnist Patrick Pelloux, told Agence France-Presse.