Prosecutors said on Monday that only 35 victims of the attack had been identified so far, leaving 49 without identification.

The process has proved particularly painstaking as officials try to avoid mistakes that led to false identifications after the November 13 Paris attacks.

Prosecutors in Paris said the identification was being conducted under an accelerated procedure set up after the Paris attacks, using medical records and DNA. There was no indication of how long the process would take.

"This process is step by step, so that everything will be guaranteed the moment that the identities will be released," French Health Minister Marisol Touraine told reporters during a visit to Nice.

The AP news agency reported that one family had spent days asking for news of a four-year-old boy whose mother had perished, leading to a confrontation with officials.

"It puts them in extreme angst, and extreme tension," Brigitte Erbibou, a psychologist, told the agency.

"It's unbearable because the more the days go by, the more they suspect the announcement will come. However, until it is announced, the wait is absolutely unbearable because there is no way to come to terms and to begin the work of the grieving process."

Touraine said that 85 people were still hospitalized, 18 people of them in a critical condition.

Selfie at the wheel

A source close to the investigation said the killer, Mohamed Lahouaiej-Bouhlel, sent a text message just before the attack in which he "expresses satisfaction at having obtained a 7.65-millimeter pistol and discusses the supply of other weapons." He also took a selfie at the wheel of the 19-ton truck he used to plow into a crowd of people celebrating Bastille Day.

While some friends and family of Lahouaiej-Bouhlel said he drank heavily and did not attend the local mosque, others spoke of a recent and swift "shift to radical Islam."

The attacker's father, who lives in eastern Tunisia, said his son had suffered from depression and that he had "no links" to religion.

With the government having declared three days of mourning for the nation's loss, questions are being asked about the fact that attacks are becoming seemingly regular.

Visits to scene of killings

It emerged on Sunday that the 31-year-old had staked out the scene of Thursday's carnage two days earlier, as well as hours before. He phoned his brother and sent a message of himself laughing as he mingled with the crowd.

An Albanian who was suspected of providing the driver with the pistol was arrested on Sunday in Nice.

Besides the Albanian, six other people were being held over the attack. Lahouaiej-Bouhlel's estranged wife was released Sunday after two days of questioning.

rc/jr (AFP, AP, dpa, Reuters)