Paris police have identified Said Kouachi, Chèrif Kouachi and Hamyd Mourad as the gunmen responsible for the terrorist attack at the Charlie Hebdo magazine office in Paris, according to a tweet from PzFeed. Two of them are brothers from Paris -- and one was apparently arrested on terrorism charges in the past, Reuters added.

The attack left 12 people dead and 11 wounded-- four of them are in critical condition, CNN reported. Thousands rallied in Paris and other cities to show they were “not afraid.” They chanted “Je suis Charlie” or “We are Charlie.”

French Interior Minister Bernard Cazeneuve said authorities are doing what it takes to "neutralize as quickly as possible the three criminals that committed this barbaric act," according to Agence France-Presse. At publication time, a manhunt was in progress to find the killers.

Pictures of the suspects surfaced on a Facebook page. Since it’s just a social media page, it cannot be confirmed if the images are authentic.

The U.S. declared solidarity with France after the outrage. “We condemn this barbaric and cowardly act. The United States and France have stood together, time and again, for the universal values we share and in opposition to the terror we deplore;'we stand ready to assist our French allies in the aftermath of today's attack,” Secretary of Defense Chuck Hagel said. President Barack Obama added: "The French people have stood up for the universal values that generations of our people have defended."

The masked men reportedly screamed "Allahu Akbar," which means “God is great,” as they shot their guns at the satirical news magazine. Charlie Hebdo, which means “Charlie Weekly,” is known for publishing cartoons of the Prophet Muhammad. It’s not the first time the magazine was attacked. It was firebombed three years ago.

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