Macron vows 'unrelenting fight' against Islamist terror

French President tells police that four staff killed by radicalised colleague fell under blows of distorted, deadly Islam which France must eradicate.

PARIS - French President Emmanuel Macron vowed an "unrelenting fight" against Islamist extremists on Tuesday as he paid tribute to the four Paris police staff stabbed to death last week by a radicalised colleague.

"We will wage an unrelenting fight in the face of Islamist terrorism," Macron told a ceremony at the police headquarters where the attack took place.

Mickael Harpon, a 45-year-old computer expert in the police intelligence-gathering department, used a kitchen knife and an oyster shucker to kill three male and one female colleague in a 30-minute rampage that ended when an officer shot him in the head.

He had converted to Islam about 10 years ago and adopted increasingly radical beliefs, according to investigators.

The killings have raised questions about how he managed to avoid detection by the police, despite having top-level security clearance.

Macron said it was "inconceivable and unacceptable" that Harpon, who had worked for the police since 2003, had managed to carry out an attack "in the very place where we pursue terrorists and criminals".

Addressing the police he said: "Your colleagues fell under the blows of a distorted, deadly Islam which we must eradicate."