Brothers linked to the Charlie Hebdo attack, and another gunman with ties to the two, were killed following separate hostage-takings in Paris that also left four hostages dead.

The violence that began in Paris on Wednesday morning left at least 20 people dead, including the three gunmen. A fourth suspect — the common law wife of the market attacker — is still at large and believed to be armed.​

Police confirmed the death of the two brothers, Said and Cherif Kouachi, who had been cornered and holding at least one hostage in a printing house northeast of Paris, in the small industrial town of Dammartin-en-Goele. That hostage was freed safely. 

A security official said the two brothers came out firing, prompting the raid on the building where they were holed up.

In the other hostage-taking, police raided a kosher grocery in the Porte de Vincennes neighbourhood in eastern Paris where a gunman, Amedi Coulibaly, had taken 19 hostages. That gunman was killed in the raid, along with four hostages, French President Francois Hollande confirmed in an address to the nation. 

"It is indeed an appalling anti-Semitic act that was committed," he said of the hostage-taking at the kosher market. An Israeli government official, recounting a conversation between Prime Minister Benjamin Netanyahu and the French president, said 15 hostages were rescued from the kosher grocery.

Prime Minister Stephen Harper called the French president Friday to offer condolences on behalf of Canadians and commend French authorities for their efforts in dealing with the hostage situations. Harper and Hollande also discussed the importance of co-operation "to counter the scourge of extremism and terrorism," a statement from the prime minister's office said.

Later Friday, a Paris prosecutor said that the four people who died in the kosher grocery were killed when Coulibaly entered the store — not when police tried to rescue them.

François Molins also said that several people have been handed preliminary charges in the investigation following the three-day rampage that has terrified France. They include family members of the three suspects killed by police Friday. 

France Newspaper Attack

A military helicopter flies over Dammartin-en-Goele on Friday as security forces moved in to capture a pair of heavily armed suspects wanted for the deadly attack on a satirical newspaper. (Thibault Camus/Associated Press)

Molins added that one of the two gunmen in the other standoff Friday was wounded in the throat in a shootout with police before being killed later in the day.

Coulibaly had threatened to kill his hostages if French authorities launched an assault on the two brothers, a police official said earlier Friday. 

France warned to be 'extremely vigilant'

Paris shut down a famed Jewish neighbourhood amid fears of further attacks and France's interior minister warned his shaken nation to remain "extremely vigilant."

A French television news network spoke directly with two of the assailants Friday before they died. BFM television said it spoke with Cherif Kouachi as he and his brother were cornered near Charles de Gaulle airport, and he told the station they were financed and dispatched by al-Qaeda in Yemen.

The station also said it spoke with Coulibaly, who said the three men were co-ordinating their moves and that he was with the militant Islamic State group. The organizations are normally rivals.

A member of al-Qaeda's branch in Yemen later claimed the group directed the attack against Charlie Hebdo "as revenge for the honour" of Islam's Prophet Muhammad. The member provided to The Associated Press a statement in English saying "the leadership of AQAP directed the operations and they have chosen their target carefully."

He says the attack was in line with warnings from the late al-Qaeda leader Osama bin Laden to the West about "the consequences of the persistence in the blasphemy against Muslim sanctities." He said the group delayed its declaration of responsibility for "security reasons."

Earlier, security forces had streamed into Dammartin-en-Goele, near Charles de Gaulle airport, in a massive operation to seize the two men at the printing house suspected of carrying out what has been referred to as France's deadliest attack in decades. One of the men had been convicted of terrorism charges in 2008, while the other had visited Yemen and a U.S. official said both brothers were on the American no-fly list.

France Newspaper Attack

Businessman Michel Catalano kept a cool head when he saw Cherif Kouachi, left, and his brother, Said arriving at an office space. He kept a young coworker hidden the entire time. (Prefecture de Police de Paris/Associated Press)

Authorities evacuated a nearby school around midday Friday after the suspects agreed by phone to allow the children safe passage, Dammartin-en-Goele spokeswoman Audrey Taupenas told The Associated Press.

"They said they want to die as martyrs," Yves Albarello, a local lawmaker who said he was inside the command post, told French television station i-Tele.

Cherif and Said Kouachi are believed to be the masked assailants who methodically opened fire on an editorial meeting of Charlie Hebdo, leaving 12 people dead in central Paris on Wednesday.

Charles de Gaulle had closed two runways to arrivals to avoid interfering in the standoff, an airport spokesman said. The town appealed to residents to stay inside.

The siege in Dammartin-en-Goele unfolded after the suspects hijacked a car early Friday in a nearby town.

Printing shop

Security forces streamed into the small industrial town near Charles de Gaulle airport in a massive operation to seize the two men at the printing house suspected of carrying out France's deadliest attack in decades. (CBC)

Tens of thousands of French security forces have mobilized to prevent a new attack since the Wednesday assault on Charlie Hebdo, which decimated the editorial staff, including the chief editor who had been under armed guard after receiving death threats for publishing caricatures of Muhammad. He and his police bodyguard were the first to die, witnesses have said.

Cherif and Said Kouachi were named as the chief suspects after Said's identity card was left behind in their abandoned getaway car. They had been holed up Friday inside CTF Creation Tendance Decouverte, a printing house. Xavier Castaing, the chief Paris police spokesman, and Taupenas

Christelle Alleume, who works across the street, said a round of gunfire interrupted her coffee break Friday 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."

Prime Minister Manuel Valls had said both suspects were known to intelligence services before the attack.

'You know who I am'

At the kosher grocery near the Porte de Vincennes neighbourhood in Paris, the gunman burst in shooting just a few hours before the Jewish Sabbath began, declaring "You know who I am," one official recounted. The attack came before sundown when the store would have been crowded with shoppers.

Paris police released a photo of Coulibaly and his wife, Hayet Boumddiene, who the official said was his accomplice.

Several people wounded when the gunman opened fire in the grocery store were able to flee and get medical care. One hundred students were locked down in nearby schools and the highway ringing Paris was closed.

With files from Reuters and CBC News