After a long day of rapidly changing information, U.S. counterterrorism officials told NBC News Wednesday night that they cannot be certain what the status is of the three suspects in the Paris attack on Charlie Hebdo magazine. Information from French sources has been contradictory, they said.
Earlier in the day, two senior U.S. counterterrorism officials told NBC News that one of the suspects in the attack had been killed and that two others were in custody. However, the officials later said the information that was the basis of that account could not be confirmed.
At least 12 people were killed in a shooting Wednesday at French satirical magazine Charlie Hebdo, which has published cartoons of the Muslim Prophet Muhammad, police told reporters.
Two police officers were among those killed. Currently, the number of injured people is thought to be around 20, of which four are critically wounded, according to Reuters.
The 12 dead included two men who went by pen names Charb - editor and cartoonist at the magazine - and the cartoonist Cabu, the Paris prosecutor's office told the Associated Press.
One suspect has been killed while the other two were taken into custody, a U.S. counter-terrorism official told NBC News. Earlier on Wednesday, French Interior Minister Bernard Cazeneuve told media that security forces were hunting for three gunmen, who fled towards the eastern Paris suburbs after holding up a car.
Officials identified Frenchmen Said Kouachi and Cherif Kouachi, brothers in their early 30s, as well as 18-year-old Hamyd Mourad, whose nationality was not immediately known, as suspects in the shooting, according to NBC News. Cherif Kouachi served 18 months in prison after a terrorism conviction for helping funnel fighter to Iraq's insurgency, NBC News reported.
An official who spoke on the condition of anonymity told the AP that the men were linked to a Yemeni terrorist network, according to NBC News.
France's terror alert was raised to the highest level after the shooting, President Francois Hollande told local media. He confirmed that several terrorist attacks had been foiled by security sources over recent weeks.
"There is possibility of other attacks and other sites are being secured," Police union official Rocco Contento told Reuters.
"Two black-hooded men entered the building with Kalashnikovs (guns)," journalist Benoit Bringer told French news channel iTELE, according to Reuters. "A few minutes later we heard lots of shots," he said, adding that the men were then seen fleeing the building.
A picture from the as-yet-unverified account of Le Monde journalist Elise Barthet apparently shows the shooters firing on a police car.
A gunman shot a wounded policeman from point-blank range before leaving the scene in a car, according to Reuters. Terrorism experts told Reuters that the shooters appeared to have carried out the attack methodically, evidenced by not only their equipment but also their getaway.
Hollande later tweeted: "No barbaric act will ever shoot down press freedom. We are a united country that can react and unite."
The attacks hit France "in the heart," Hollande said while addressing the nation around 2 ET on Wednesday. He said that the shooters attacked "the ideal of justice and peace."
"Freedom is always stronger than barbarism," Hollande said.
He added that flags in the country would fly at half mast tomorrow.
Charlie Hebdo is renowned for courting controversy. In 2012 it published cartoons of the Muslim prophet Muhammad, forcing France to temporarily close its embassies and schools in more than 20 countries amid fears of reprisals.
Its offices were also firebombed in November 2011 after publishing the Muhammad cartoon. Offices had been under police protection since the incident, according to Reuters.
The magazine's last tweet before the shooting was of a cartoon of Abu Bakr al-Baghdadi, leader of terrorist organization ISIS. No group has yet claimed responsibility for the attack, Reuters reported.
A series of rallies under the slogan "Je Suis Charlie" (I am Charlie), took place around Europe on Wednesday evening.
Obama in a statement pledged to assist France in finding the gunmen and larger networks responsible for the "cowardly" and "evil" attack, according to Reuters. U.S. authorities are aiding French law enforcement in investigating the attack, FBI Director James Comey said from the International Conference on Cyber Security in New York.
"The fact that this was an attack on journalists, an attack on our free press, also underscores the degree to which these terrorists fear freedom of speech and freedom of the press,'' Obama said.
Obama added that he would encourage U.S. Secretary of State John Kerry and American travelers abroad to stay vigilant. Calling the shooting "a vicious act of violence," Kerry criticized attempts to quell free expression and voiced American solidarity with France.
U.K. Prime Minister David Cameron, who was with Merkel on Wednesday for a previously scheduled diplomatic meeting, decried the "appalling terrorist outrage."
"We must never allow the values that we hold dear—democracy, freedom of speech—to be damaged by these terrorists," Cameron said.
Britain's Queen Elizabeth II sent a message to Hollande offering condolences in the wake of the shooting.
- NBC News contributed to this report