The attacks threaten to stoke Islamophobia in a country that has the biggest Muslim population in Europe and may bolster support for the anti-immigration National Front party. They prompted other countries to bolster security, with the U.K. stepping up border security and Spain raising its terror alert.

Around the world, tens of thousands of people rallied yesterday in support of the victims, gathering at public squares and French embassies from New York to Hong Kong. In Paris, more than 10,000 people thronged the place de la Republique, holding candles and signs that said “Je suis Charlie” -- I am Charlie.

Armed and Dangerous

At least 12 people died at the Charlie Hebdo office in eastern Paris, and 11 people were injured. No link has been established between those killings and today’s shootout just outside the capital, police said.

In today’s incident, an unarmed policewoman was killed and a traffic agent was injured after an assailant shot them with a pistol and an automatic weapon. The attacker remains at large.

In another troubling twist, a shot was fired at a mosque in Le Mans today and four plaster grenades thrown into its courtyard.

In the Charlie Hebdo case, Cazeneuve said seven people are being questioned, with the two suspected perpetrators -- brothers Said Kouachi, 34, and Cherif Kouachi, 32, -- on the run. They are armed and dangerous, police said.

The youngest suspect in the attack turned himself in, a spokeswoman for the Paris prosecutor said. The 18-year-old high-school student may have been confused with another person. Classmates tweeted that yesterday that he was at his school in Charleville-Mezieres, 230 kilometers (135 miles) from Paris, and that he has nothing to do with radical Islam.

Police Protection

Police had seen no indication that the suspected assailants were planning an assault, according to Cazeneuve. Cherif Kouachi had served time in prison for participating in a jihadist recruitment cell.

Jean-Louis Bruguiere, a former anti-terrorist prosecutor, said in an interview that Islamic radicals once came out of organizations whose e-mails and money transfers could be tracked, or were radicalized in underground mosques that could be monitored. Now they are recruited through social media.

France is on the highest terrorist alert, with protection extended to places of worship and media outlets.

Yesterday’s assault was carried out by two masked men brandishing AK-47 Kalashnikov rifles, with at least one shouting “Allahu Akbar,” or “God is great” in Arabic.

‘Exceptional Barbarity’

“France is in a state of shock after this terrorist attack,” said President Francois Hollande. “An act of exceptional barbarity has been perpetrated against a newspaper, against liberty of expression, against journalists.”

Thousands of people flocked into town squares across France last night to defend what they said were values dear to them.

“I came here to show we don’t cede to terror,” said Elie Benchimol, 23, an economics student who was at the Place de la Republique in Paris. “France must continue to define itself as a country of freedom of expression and rule of law.”

The dead included eight journalists, a guest at the weekly, a maintenance man and two policemen. The magazine’s most renowned cartoonists -- Cabu, Charb, Tignous and Wolinski -- were among those killed.

France’s last major terrorist violence came in 1995, when bombings struck public places between July and October, including the Saint Michel metro station in the heart of Paris. Bombs also exploded in the Place de l’Etoile. In all, eight were killed and about 200 were injured. The bombings were blamed on an Algerian rebel group.

In 2012, Mohammed Merah, a 23-year-old Frenchman of Algerian descent, murdered seven people, including three children and a teacher at a Jewish school in Toulouse.

“We can’t accept this madness,” Dalil Boubakeur, the Paris Mosque’s rector, said yesterday. “We want to live in peace.”

--With assistance from Tara Patel and Fabio Benedetti-Valentini in Paris.

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