A man who killed two police officials in Paris last night had a "hit list" of VIPs, police and rappers, the Paris prosecutor has said.
The killer, 25-year-old Larossi Abballa, had pledged allegiance to the so-called Islamic State group three weeks ago, Francois Molins told a news conference.
Earlier, a police source said two people had been detained in connection with the attack, and Mr Molins confirmed that a third person had also been taken into custody as part of the investigation into the double murder.
French President Francois Hollande this morning said the killing of the policeman and his partner was "unquestionably a terrorist act".
The couple were "murdered in cowardly fashion by a terrorist," Mr Hollande told reporters after the overnight attack at the couple's home northwest of Paris.
He said: "France is facing a very significant terrorist threat."
The suspect had been sentenced in 2013 for taking part in a jihadist organisation with links to Pakistan, sources close to the investigation said.
Sources said he had been sentenced to a three-year term, six months of which were suspended, for "criminal association with the aim of preparing terrorist acts," in a trial with seven other defendants.
French Interior Minister Bernard Cazeneuve described the killing as an "abject act of terrorism".
Mr Cazeneuve said the investigation was continuing as quickly as possible to, as he put it, put further accomplices out of action.
Witnesses told investigators the man may have shouted "Allahu akbar" [God is greatest] as he stabbed the 42-year-old policeman outside his home before locking himself inside with the woman and the couple's three-year-old son.
Loud detonations were heard at the scene as elite RAID police moved in following failed negotiations with the attacker, who claimed allegiance to IS while talking to officers, sources close to the inquiry told AFP.
The suspect was shot dead.
"Negotiations were unsuccessful, a decision was made to launch an assault," Interior Ministry spokesman Pierre-Henry Brandet said.
The couple's son was "in shock but unharmed," a prosecutor added, saying the little boy was receiving medical attention.
A news agency linked to IS said the attack had been carried out by an "Islamic State fighter", days after posting a similar claim following the massacre at a gay nightclub in Orlando, Florida.
