Five Arrested over Deadly Knife Attack on Paris Police HQ

Police on Monday staged raids at three separate sites in the city's northern suburbs, according to judicial sources, Al Jazeera reported.

Michael Harpon, a 45-year-old technician, had stabbed to death three police officers and an administrative worker on October 3 before being shot and killed at the scene.

Authorities say the man was in touch with suspected members of the ultra-conservative Salafist movement.

The attacker's widow was arrested for questioning after the attack but was released without charge three days later.

The killings raised serious questions about how police failed to notice various signs of Harpon's radicalization in recent years, despite France being on high alert over a wave of deadly attacks.

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