PARIS - Death toll in Nice attack, in which a man drove a heavy truck into crowds on July 14 in the southern French city, rose to 85, Christian Estrosi, president of the Rivera region announced on Thursday.

According to the regional daily Nice Matin, Peter Hattermann, 56, succumbed to his injuries. His wife and 13-year-old son were also killed in the attack that occurred in the Promenade des Anglais during the Bastille Day celebrations.

His 14-year old daughter was still hospitalized, it added.

"All my thoughts for the girl, the family and relatives of Peter Hattermann who just died. (The) 85th (victim) disappeared after the attack of Nice," Estrosi, former mayor of Nice, tweeted.

On July 14, Mohamed Lahouaiej Bouhlel plowed a heavy truck into crowds that were celebrating National Day in Nice. The truck careered 2 km through mass of revelers before being stopped by police units who also shot dead the driver.

The Islamic State (IS) claimed responsibility for the attack.

Probing showed the 31-year delivery man had prepared his act for months with the help of accomplices. It also showed his "certain, recent interest to radical jihadist movements."