VIA| DEVELOPING — The man widely known as the suspected mastermind of last Friday’s Paris attacks that killed 129 people, who bragged that he could always stay one step ahead of Western intelligence, was killed in the police raid north of Paris Wednesday.

Officials also confirmed that his cousin was killed, when she apparently blew herself up.

Abdelhamid Abaaoud, 27, had been linked to as many as four thwarted attacks since this spring, including the plot to kill passengers on a Paris-bound high-speed train in August, a plot that three young Americans helped foil. He was identified from skin samples after the Saint-Denis apartment raid, the French prosecutor’s office reported Thursday.

Abaaoud had claimed he successfully moved back and forth from Europe to Syria coordinating terror attacks, and narrowly escaped a January police raid in the Belgian city of Verviers. “Allah blinded their vision and I was able to leave… despite being chased after by so many intelligence agencies,” he told the ISIS magazine Dabiq.

Two counterterrorism sources tell Fox News his death marks a major advance for the investigation, but add they are operating on the premise that more senior suspects connected to the plot are still out there.

They describe Abaaoud as the “Mohammed Atta” of the Paris attacks, the “tactical guy” who identified and pulled together the operatives, in the same way the lead hijacker kept the 9/11 teams on course.

They emphasize that based on his skill set and experience, Abaaoud was not the strategic planner, in the same way Khalid Sheikh Mohammed was for the 9/11 attacks. The Paris massacre involved a plot or plots with multiple layers and upwards of 20 players, according to the chairman of the House Homeland Security Committee, Texas Republican Michael McCaul.

Police say they launched Wednesday’s operation after receiving information from tapped phone calls, surveillance and tipoffs suggesting that Abaaoud was holed up in the apartment. Investigators said it was still unclear how he died. Eight other people were arrested.

French authorities did not know he was in Europe before the massacre, France’s interior minister Bernard Cazeneuve said Thursday. He demanded Europe do everything in its power to “vanquish terrorism.”

During the raid, according to one police official, an officer approached Abaaoud’s cousin, Hasna Aitboulahcen, and asked her, “Where is your boyfriend?” She responded angrily: “He’s not my boyfriend!” Then there was an explosion.

The bodies recovered in the raid were badly mangled, with a part of the woman’s spine landing on a police car, complicating formal identification. Her possible role in the Paris massacre was unclear.

The manhunt for at least two other suspects believed to have participated in the attacks continued Thursday. Police have identified one of them as Salah Abdeslam, who grew up in the same Belgian district as Abaaoud, the Brussels suburb of Molenbeek.

Also Thursday, authorities say they detained nine people during as many raids in the Brussels area. Two of the detentions were related to Friday’s massacre, and seven others involved the entourage of Bilal Hafdi, one of the suicide bombers at the stadium, but related to issues from before the Paris attacks, according to a prosecution official who spoke on condition of anonymity.

The official refused to provide any details on the two detainees linked to the Paris attacks. There are currently already two suspects in custody charged with terrorist murder and belonging to a terrorist group.

Friday’s attacks wounded hundreds of people, and left Europe and much of the world on edge French Prime Minister Manuel Valls warned Thursday that associates of the attackers could use chemical and biological weapons, as he urged Parliament to extend a state of emergency.

Valls said “terrorism hit France, not because of what it is doing in Iraq and Syria … but for what it is.” The French Senate is set to vote Friday on prolonging the nation’s state of emergency by three months.

The state of emergency expands police powers to carry out arrests and searches, and allows authorities to forbid the movement of people and vehicles at specific times and places.