THE two brothers who carried out the deadly storming of Charlie Hebdo are cornered inside an industrial building with a hostage and have told police they are ready to "die as martyrs".
One of the Kouachi brothers turned up at the printing factory and pretended to be a police officer.
He then told a worker: "Get out of here, we don't kill civilians."
Hundreds of French security forces backed by a convoy of ambulances streamed into Dammartin-en-Goele, northeast of Paris in a massive operation to seize the men who carried out France's deadliest terror attack in decades.
At least three helicopters hovered above the small industrial town, near Charles de Gaulle airport.
Two runways were closed to arrivals to avoid interfering in the stand-off, an airport spokesman said.
Schools went into lockdown and local residents were ordered to stay at home, switch off the lights and stay away from their windows.
The stand-off follows a car chase on the N2 motorway in which gunshots were fired between the men and police as their stolen car headed towards Paris.
Tens of thousands of French security forces have mobilized to prevent a new terror attack since the Wednesday assault on the offices of Charlie Hebdo in the heart of Paris left 12 people dead, including the chief editor and cartoonist who had been under armed guard with threats against his life after publishing caricatures of the Prophet Muhammad.
His police bodyguard also died in the attack, which took place during an editorial meeting.
Brothers Cherif (32) and Said Kouachi (34) were named as the chief suspects after one of the two apparently left Said's identity card behind in their abandoned getaway car.
Police now also believe the killing of a Paris policewoman yesterday is linked to the Charlie Hebdo attack. French radio station Europe 1 reported today that the gunman was a known associate of Cherif Kouachi.
The two Kouachi brothers were holed up today inside CTF Creation Tendance Decouverte. Xavier Castaing, the chief Paris police spokesman, and town hall spokeswoman Audrey Taupenas, said they appeared to have one hostage - believed to be a woman - inside the printing house with them.
Christelle Alleume, who works across the street, said that a round of gunfire interrupted her coffee break this morning.
"We heard shots and we returned very fast because everyone was afraid," she told i-Tele. "We had orders to turn off the lights and not approach the windows."
A salesman named as Didier told the radio station France Info that he believed he had encountered and shaken the hand of one of the terrorists today in Dammartin-en-Goele.
He said when he arrived to meet a customer called Michel this morning he met a heavily-armed man dressed in black and wearing a bullet-proof vest. He took the man to be a police officer but became suspicious because of what he said to him.
"I was in front of the business, I shook Michel's hand and then he said to me 'I am the police. Go, we do not kill civilians'. I guessed that it was one of the terrorists. After I left, Michel shut the gate behind me," he said.
"I knew there was something wrong. I decided to call the police. It could have been a police officer if he had not said to me 'we do not kill civilians'.
"I have been very lucky this morning."
French Prime Minister Manuel Valls has said both terrorists were known to intelligence services.
A senior US official said yesterday that the elder Kouachi had traveled to Yemen, although it was unclear whether he was there to join extremist groups like al-Qaida in the Arabian Peninsula, which is based there.
The younger brother, Cherif, was convicted of terrorism charges in 2008 for his links to a network sending jihadis to fight American forces in Iraq. Both were also on the US no-fly list, a senior US counterterrorism official said. The American officials also spoke on condition of anonymity because they were not authorized to discuss foreign intelligence publicly.
French President Francois Hollande called for tolerance after the country's worst terrorist attack in decades.
"France has been struck directly in the heart of its capital, in a place where the spirit of liberty - and thus of resistance - breathed freely," Hollande said.
Nine people, members of the brothers' entourage, have been detained for questioning in several regions.
In all, 90 people, many of them witnesses to the grisly assault on the satirical weekly Charlie Hebdo, were questioned for information on the attackers, Interior Minister Bernard Cazeneuve said in a statement.
A third suspect, 18-year-old Mourad Hamyd, surrendered at a police station on Wednesday evening after hearing his name linked to the attacks. His relationship to the Kouachi brothers was unclear.
The Kouachi brothers - born in Paris to Algerian parents - were well-known to French counterterrorism authorities. Cherif Kouachi, a former pizza deliveryman, had appeared in a 2005 French TV documentary on Islamic extremism and was sentenced to 18 months in prison in 2008 for trying to join up with fighters battling in Iraq.
Charlie Hebdo had long drawn threats for its depictions of Islam, although it also satirized other religions and political figures.
The weekly paper had caricatured the Prophet Muhammad, and a sketch of Islamic State's leader was the last tweet sent out by the irreverent newspaper, minutes before the attack. Nothing has been tweeted since. Eight journalists, two police officers, a maintenance worker and a visitor were killed in the attack.
Charlie Hebdo are planning a special edition next week, produced in the offices of another paper.
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