French investigators arrested two more people on Sunday as they pieced together details about the motives and preparations of the Tunisian who rammed a truck into a crowd in an attack that killed 84.
Mohamed Lahouaiej-Bouhlel visited the Nice promenade with his rented truck on the two days before he smashed the vehicle into a crowd of people watching Bastille Day fireworks in the French Riviera city on Thursday night, according to a source close to the probe.
Bodies were left strewn across the storied seafront in the grisly attack by a man described by those who knew him as a loner with tendencies towards violence and depression.
While some family and friends had described the 31-year-old as someone who smoked, drank and never went to the mosque, others questioned by police indicated "a recent swing to radical Islam", said a police source.
However, there has been no overt evidence linking him to the Islamic State group, which on Saturday claimed the attack.
In Nice, many people were still desperately looking for news of their loved ones among the dead and 121 still hospitalised.
"We have no news, neither good nor bad," said Lithuanian Johanna, who was looking for her two friends, aged 20.
At least 10 children were among the dead as well as tourists from the United States, Ukraine, Switzerland and Germany and about 10 from Russia, a local Russian association said.
A man and a woman were arrested on Sunday and were being held alongside four people arrested earlier. Lahouaiej-Bouhlel's estranged wife was released after two days of questioning.
One of those held is a 22-year-old, suspected of lending logistical support to Lahouaiej-Bouhlel, said his lawyer Jean-Pascal Padovani.
He said the two had only known each other a few months and that "there is no material evidence" against his client.
Radicalised very quickly
While he had a record of being a petty criminal, Lahouaiej-Bouhlel had never appeared on the radar of intelligence services for links to radical Islam.
Interior Minister Bernard Cazeneuve on Saturday said the father-of-three "seemed to have been radicalised very quickly, from what his friends and family" have told police.
People who went to the same gym as Lahouaiej-Bouhlel, described him as "conceited" and someone who "would flirt with anything that moved.”
The IS said one of its "soldiers" carried out the attack "in response to calls to target nations of coalition states that are fighting [IS]".
Mr. Cazeneuve described the massacre as "a new kind of attack" which highlighted "the extreme difficulty of the anti-terrorism fight".
"We are now confronted with individuals open to IS's message to engage in extremely violent actions without necessarily having been trained or having the weapons to carry out a mass [casualty] attack," he said.
Patriots called to volunteer
France's third major terrorist attack in the past 18 months has left Paris fending off criticism over security failures and scrambling to reassure its citizens they are protected.
Mr. Cazeneuve called for volunteers to boost security forces who have already been reinforced and on high alert under an eight-month state of emergency.
"I want to call on all French patriots who wish to do so, to join this operational reserve."
France's "operational reservists" include citizens with or without military experience as well as former soldiers.
