Described by his neighbours as a handsome but frightening man, Mohamed Lahouaiej Bouhlel, who killed at least 84 people in the French city of Nice by driving his truck into a crowd late on Thursday, was convicted only once before: for road rage.
Bouhlel ploughed a truck into crowds celebrating Bastille Day, in what President Francois Hollande called a terrorist act by an enemy determined to strike all nations that share France's values.
While he had several run-ins with the law previously, Bouhlel, a 31-year-old Nice resident born in Tunisia, was not on a watch list of French intelligence services as a suspected militant.
He was convicted for the first time in March this year, French Justice Minister Jean-Jacques Urvoas said.
"There was an altercation between him and another driver and he hurled a wooden pallet at the man," Urvoas said.
As it was his first conviction, Bouhlel was given a suspended sentence and had to contact police once a week, which he did.
Tunisian security sources told Reuters Bouhlel had last visited his hometown of Msaken four years ago.
He was married with three children, but had marital problems, the Tunisian sources said.
He was not known by the Tunisian authorities to hold radical views, and had held a French residence permit for the past 10 years without obtaining French nationality, Tunisian sources said.
Neighbours in the residential neighbourhood in northern Nice where Bouhlel lived said he had a tense personality and did not mingle with others.
"I would say he was someone who was pleasing to women," said neighbour Hanan.
"But he was frightening. He didn't have a frightening face, but ... a look. He would stare at the children a lot," he added.
His home town Msaken close to the coastal city of Sousse, where a gunman killed 38 people, mostly British holidaymakers, on a beach a year ago.
Many residents of the town have migrated to Nice, where the Tunisian community numbers about 130,000 people, according to Tunisian state news agency TAP.
The Tunisian government issued a statement condemning Thursday's attack "in the strongest possible terms".