Nice terrorist: Investigators still want to know, 'Why did he do it?'

NICE, France — As French investigators try to answer why Mohamed Lahouaiej Bouhlel drove a truck on a murderous rampage into the crowds celebrating Bastille Day, details on the troubled life of the 31-year-old delivery driver have started to emerge.

Although the Islamic State claimed Saturday that it inspired Thursday's attack in this French Riviera city and described Bouhlel as “a soldier of the Islamic State,” nothing in the behavior of the Tunisian-born French resident betrayed any suspicions of radicalization. Bouhlel drove his truck into the crowd for a mile, killing 84 and injuring 200 before police shot him to death.

ISIL claims responsibility for inspiring Nice attack; 5 detained by police

Bouhlel did not appear to be a devout Muslim. He dressed in Western style, drank alcohol, frequented nightclubs and didn’t pray or fast during Ramadan, according to relatives of his wife and friends who spoke to the French daily Libération. "He was mad. He drank, ate pork and didn't pray," said a family friend identified only as Walid.

Born in M’saken, in the outskirts of the Tunisian coastal town of Sousse, on Jan. 3 1985, Bouhlel moved to France eight years ago, according to police. He settled down in northern Nice, where the relatives of his wife, also of Tunisian origin, live.

The couple had three children, two daughters and a boy, aged between 5 years and 18 months, police said.

Life in their apartment in the mixed, high-rise neighborhood was blighted by episodes of domestic violence.They became so serious that his wife decided to report him to the police, a relative who used the pseudonym Nacer told Libération.

Bouhlel was also known to the police for other episodes of violence and threats, such as scuffles with neighbors and acquaintances, but had not appeared on the radar screen of anti-terrorist intelligence, police said.

His criminal record included only a six-month suspended sentence after he hit a driver during an altercation over a parking spot in January 2016, according to police.

Two years ago, he separated from his wife and moved across town into a studio apartment in a four-story building in the Abattoirs, a modest neighborhood in eastern Nice. There, he kept a low profile with his new neighbors.

“I have only said bonjour to him two or three times, that’s all,” said Gagik Galstyan, a neighbor in the unassuming dusty-yellow building at 62 Route de Turin.

Others said Bouhlel wasn’t friendly, was a heavy drinker and gave the impression of being “lost” and unstable, but certainly not a radicalized terrorist.

“He smelled of alcohol in the middle of Ramadan. He didn’t look religious either, he didn’t have a beard,” said Jasmine Ghouma, a 38-year-old hairdresser who lives on the ground floor with two children.

“Whenever we said good morning, he never replied, he just stared. He never spoke to anyone,” she added. “We are in shock. It’s shocking to find out that your neighbor is a killer.”

In an interview with Tunisian radio station Mosaïque FM, Bouhlel’s brother, who was not identified by name, said they had spoken on the phone Thursday and that while Bouhlel had mentioned his marital problems, he said he was planning to travel to Tunisia soon for the wedding of a relative.

Bouhlel’s father told French radio RTL that his son had gone through a difficult period in 2004 and had been treated by a psychiatrist. The father also was not identified by name.

Bouhlel didn’t leave any messages in his apartment, which police officers were still searching Saturday for evidence, or in the truck where he died. Police found his identity papers and a number of fake weapons, including two replica assault rifles, in the truck, police said as they left his apartment.

Police assume the attack was premeditated, because Bouhlel had rented the refrigerated truck on Monday afternoon from a vehicle rental agency in nearby Saint-Laurent-du-Var, police said

As the investigation into the attack continues, five people close to Bouhlel remain in police custody, including his wife, according to French daily newspaper Le Monde.

French Interior Minister Bernard Cazeneuve said at a press briefing in Paris on Saturday that Bouhlel "seems to have become radicalized very quickly," a fact that underscored the “extreme difficulty of the fight against terrorism.”

In addition to monitoring radicalized French youth, intelligence services have now to contend with a number of troubled individuals who are at risk of turning overnight into ”lone-wolf” terrorists.

In June 2015, Yassin Salhi killed his boss and pinned his severed head to a fence at an industrial gas factory in Lyon and surrounded it with Islamic flags. Before he committed suicide in prison a few months later, he maintained that he had been motivated by a grudge against his employer, not by religion.

In January, on the anniversary of the mass shootings at the office of the Charlie Hebdo satirical magazine, a man carrying the identity card of a Moroccan national was killed in Paris as he tried to storm a police station armed with a meat cleaver and a fake suicide belt. He was carrying a piece of paper pledging allegiance to the Islamic State.