PARIS (AP) — The Belgian extremist suspected of masterminding the deadly attacks in Paris died a day ago along with his female cousin in a police raid on a suburban apartment building, French officials said Thursday, adding it was still not clear exactly how he died.

The body of Abdelhamid Abaaoud, 27, was found in the building targeted Wednesday in the chaotic, bloody raid in the Paris suburb of Saint-Denis and was identified based on skin samples, the Paris prosecutor’s office said Thursday.

Abaaoud ended up near Paris after reportedly being in Syria but officials have not said how he managed to travel across so many borders en route to the French capital. In addition, authorities have not detailed his exact whereabouts or actions during the deadly rampage that killed 129 people last week in Paris.

Interior Minister Bernard Cazeneuve said France did not know before last week’s deadly attacks that Abaaoud was in Europe, but said he was believed to be behind four of six attacks thwarted since spring by French authorities.

Three police officials have told The Associated Press that a woman who died in the police raid was Abaaoud’s cousin. One said the woman, Hasna Aitboulahcen, is believed to have detonated a suicide vest Wednesday in the building after a brief conversation with police officers.

The official confirmed an audio recording, punctuated by gunshots, in which an officer asks: “Where is your boyfriend?” and she responds angrily: “He’s not my boyfriend!” Then loud bangs are heard.

The bodies recovered in the raid were badly mangled, with part of Aitboulahcen’s spine landing on a police car, slowing down the identification process, according to one of the officials.

The three all spoke on condition of anonymity because they were not permitted to divulge details of the investigation.

French police launched the operation after receiving information from tapped phone calls, surveillance and tipoffs suggesting that Abaaoud was holed up in the apartment. Eight people were arrested in the raid.

In Belgium, authorities launched six raids in the Brussels region Thursday linked to Bilal Hadfi, one of the three suicide bombers who blew themselves up outside the Stade de France.

An official in the Belgian federal prosecutor’s office told The Associated Press the raids were taking place in the suburb of Molenbeek and other areas of Brussels. The official, who spoke on condition of anonymity because the investigation is continuing, said the actions were focusing on Hadfi’s “entourage.”