The man who killed a French police couple at their home near Paris was responding to calls by so-called Islamic State (IS) “to kill infidels, police said on Tuesday.
Larossi Abballa, who was killed in a shootout with police, was loyal to IS leader, Abu Bakr al-Baghdadi, police said.
A police commander and his partner were stabbed to death at their home.
Their three-year-old child survived, the BBC reports.
The killings were “a terrorist act,” President Francois Hollande said.
France still faced “a significant threat,” he added.
The attacker was killed in a police assault on the house in Magnanville, about 55km (35 miles) north-west of the French capital.
He had spent time in jail over jihadist links and had a list of targets including public figures, police said.
He had also been under recent police surveillance, including a wiretap, media reports said, quoting police sources.
Paris Prosecutor Francois Molin said Abballa had pledged his loyalty to the IS leader during negotiations prior to the police assault on Monday.