Two of the three suspects wanted over an attack on the offices of a French satirical magazine on Wednesday are still at large.
One of the suspects - who are all French nationals - turned himself in to a police station close to the border with Belgium.
The suspected Islamist militant attack on the Paris offices of Charlie Hebdo - a publication that has previously enraged Muslims by depicting the Prophet Muhammad in their cartoons - left 12 people dead, including two police officers.
The gunmen were masked and armed with AK-47s when they entered the building and killed a janitor before proceeding to kill eight journalists who were having an editorial meeting at the time. The gunmen apparently targeted employees who helped publish the controversial cartoons by asking the specific names of their victims, a source told NBC news.
They killed editor and cartoonist Stephane Charbonnier, columnist Bernard Maris, and three more cartoonists. A security officer, a police officer, and a guest were also killed. Eleven were injured and four of them were in critical condition, officials reported.
It is believed that the magazine was targeted because of its flagrant criticism of the Islamic faith. The weekly had previously published cartoons mocking the Prophet Muhammad and its last tweet before the attack poked fun at Abu Bakr al-Baghdadi, leader of the Islamic State, which has seized large areas of Syria and Iraq.
Distressing footage captured by a witness showed one of the assailants walk over to a police officer lying wounded on the ground and shoot him in the head.
Reuters reports that a police document names the suspects as Said Kouachi, born in 1980, Cherif Kouachi, born in 1982, both from Paris, and Hamyd Mourad, born in 1996. It is understood that Mourad turned himself in.
The attack has horrified France, a country fiercely protective of its right to self-expression and liberty, and thousands of people turned out for vigils in tribute to the victims. Members of the crowd held cards with the slogan 'Je suis Charlie' - French for 'I am Charlie'.
In response to the attack, thousands of Parisians walked the streets with lighted candles, gathering at the monument Place de la Republique where they chanted "Charlie! Liberty!". The three statues representing the pillars of France's values - Liberty, Equality and Fraternity - were covered with posters and candles.
"They want to scare French citizens and prohibit any criticism of religion, so here we are to remind them that religion can be freely criticised," said Sasha Reingewirtz, 28, president of the Jewish Students Union.
French President Francois Hollande visited the scene of the tragedy on Tuesday and has declared a national day of mourning for Thursday.
The government raised the terrorism threat to its highest level but assured the French people that security was being doubled across the city.
"Today the French Republic as a whole was the target," said President Hollande in a televised address on Wednesday evening.
An anonymous officer told the Associated Press that all three suspects were connected to a Yemeni terrorist network.
Cherif Kouachi is suspected of having a long-standing involvement with terrorist groups. He was arrested in Paris back in January 2005 and was suspected to be one of the operation leaders aiding Iraq with young volunteers to fight US-led forces. According to authorities, the operation was linked to the 19th Arrondissement Network, which was based in Paris and home to many Muslim families.
In 2008, he was also convicted of terrorism charges on the grounds that he provided fighters to Iraq's insurgency. He was sentenced to three years in prison, of which 18 months were suspended.
US President Barack Obama was among the world leaders condemning the attack. "Our thoughts and prayers are with the victims of this terrorist attack and the people of France," he said.
The US has offered assistance to France as it hunts the killers and underscored its "solidarity with France, America's oldest ally".
