Four men have been arrested by Saturday over the terrorist attack in Nice that killed at least 84 people, local media quoted judicial sources as saying.

Among the four men linked to the killer, one was arrested Friday and three others on Saturday morning. The driver's ex-wife has also been arrested.

At around 10:30 p.m. (2030 GMT) on Thursday, 31-year-old French citizen of Tunisian origin Mohamed Lahouaiej-Bouhlel drove a truck into a crowd celebrating the French national day in the southern city of Nice. At least 84 people were killed.