PARIS (News Desk) – French law enforcement agencies have detained as many as three people in connection with the Nice truck attack which claimed 84 lives during Bastille Day celebrations.

All of the arrested persons were close friends of the attacker, who was driving the truck involved in the terrorist attack and was shot dead by the police. His wife was also among the two people previously held by officials.

Initially, the investigators identified the attackers as 31-year-old French national of Tunisian origin named Mohamed Lahouaiej Bouhlel. However, they are still probing into the authenticity of the Islamic State’s claim that the attacker was one of their fighters.

A statement issued by the pro-IS news agency, Amaq News, said: “The person who carried out the operation in Nice, France, to run down people was one of the soldiers of Islamic State.”

“The attack was carried out in response to the calls to target the nationals of the states that are part of the coalition fighting Islamic State group in Syria and Iraq,” it added.

Meanwhile, the attacker’s sister, talking to Reuters from her residence in Tunisia, said that her brother was facing psychological problems when he moved to France some ten years ago.

Bouhlel’s friends and close relatives also said that he was not a religious person and that there was no clear evidence of his possible radicalisation.

On the other hand, French Interior Minister Bernard Cazeneuve said that Mohamed Lahouaiej Bouhlel could have undergone a rapid change. The testimonies suggest that there was something that suddenly pushed him to carry out the attack, he said.