People sing the French national anthem at Place de la Republique as France observes three days of national mourning for the victims of the terror attacks on Nov. 15, 2015 in Paris, France. 
Photo by Jeff J Mitchell/Getty

Massacre in Paris: What we know about the attackers

As Paris reels from Friday’s series of terrorist attacks across the city that killed more than 120 people and injured at least 350, a clearer picture is beginning to emerge of how the violence unfolded and who was behind it. French authorities are continuing to track down any potential accomplices, but here’s what we know about the attackers so far:

ISIS has claimed responsibility: The terrorist group known as ISIS issued a statement on Saturday claiming responsibility for the attacks, calling it a “blessed invasion.” French President Francois Hollande has also said ISIS was behind the attack and called it an “act of war.”

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At least seven attackers are dead: Paris Prosecutor Francois Molins said seven terrorists — who were heavily armed and wearing explosives — were killed on Friday in connection with massacre. A French official confirmed to NBC News the names of two of the attackers, Ismail M. and Abbdul Akbak B, after they were identified by French media. One is reportedly a radicalized French national while the other was Syrian-born.

They worked in three teams: Molins said the extremists worked in three groups. He elaborated by saying one team of three suicide bombers went to the Stade de France for the France-Germany soccer game, another group armed with Kalashnikovs drove around to several locations in Paris, including restaurants and bars, while a third went to Le Bataclan theater — where at least 89 people were killed during a concert there by the band Eagles of Death Metal.

They used nearly identical explosive devices: According to Molins, the attackers used explosive waistcoats and belts with the same batteries and push-button detonators. They also all used the explosive TATP, which was also used by “shoe bomber” Richard Reid in 2001.

There’s an ongoing manhunt in Paris: French security officials said on Sundaythat they are looking for a French man they believe was involved in the attacks. The man had rented a Belgian-registered black Volkswagen Polo which was found abandoned by the terrorists who opened fire at Le Bataclan. NBC News reported that he was identified by officials as Salah Abdeslam, 26, from Brussels.

Arrests have been made in Brussels: Belgian authorities have said they have arrested at least five people in the immigrant district of Molenbeek in connection with the deadly attacks. Those people have not been identified.

Concern one attacker entered Europe by hiding among refugees: Some officials have expressed alarm that attackers may have come into Europe hiding among the wave of refugees being allowed to come to the country in light of violence in the Middle East. Serbia’s Ministry of Interior told NBC News that one suspect had requested asylum last month at the Presevo border crossing. 

France, ISIS, Paris and Paris attacks

Massacre in Paris: What we know about the attackers