The man who used a 20-ton truck to plow down hundreds of people in Nice, killing 84, somehow became rapidly radicalised and hadn’t shown up on any anti-terrorist intelligence radar, French Interior Minister, Bernard Cazeneuve, said.

The minister said Mohamed Lahouaiej Bouhlel, 31, had had no record of making militant statements and was not known to the intelligence services.

It seems he became radicalised very quickly,” Cazeneuve said, without offering specifics.

“This is a new type of attack,” Cazeneuve said. “We are now confronted with individuals that are sensitive to the message of ISIS and are committed to extremely violent actions without necessarily being trained by them.”

A statement from ISIS’ media group, Amaq Agency, said that an ISIS “soldier” carried out the attack in Nice.

The statement, which was posted by ISIS supporters, said a security source told the agency “the person who carried out the run-over in Nice, France, is one of the Islamic State soldiers and carried out the operation in response to calls to target nationals of the coalition which is fighting the Islamic State.”

The wording of the statement – not claiming the attack as an outright act of ISIS, but noting that the attacker was responding to calls to act against the coalition – mirrors ISIS’ language in statements after the nightclub shooting in Orlando, when it claimed gunman Omar Mateen as a “soldier.” Forty-nine people died in the June 12 massacre.

French prosecutor, François Molins, said on Friday that the attack in Nice fits with calls that “terrorist organisations regularly give out on their videos and elsewhere.”

As the investigation continued, French authorities questioned five people on Saturday. Among them was Bouhlel’s former wife, who was taken into custody on Friday, the anti-terrorism prosecutor’s office said. The other four are men.

Bouhlel, a resident of Nice, was born in Tunisia but had a permit to live and work in France.

While Cazeneuve said no evidence had yet been found to tie Bouhlel to jihadism, a source close to the investigation told CNN that a phone number belonging to Bouhlel cropped up in a counter-terrorism investigation into an associate of Omar Diaby, a 41-year-old Senegalese jihadi who lived in Nice before traveling to Syria.