At least three people were stabbed to death on Thursday in the French city of Nice, with the Mayor saying that the incident pointed to a "terrorist attack at the heart of the Notre-Dame basilica".
According to the police, one woman was beheaded in the attack, while the suspect was detained shortly after the attack, the BBC reported.
Addressing the media, Nice Mayor Christian Estrosi said that the suspect had "repeated endlessly 'Allahu Akbar' (God is greatest) when he was being treated at the scene", adding that one of the three victims was the caretaker at the basilica.
The country's national anti-terror prosecutors have opened a murder inquiry.
Meanwhile, a minute's silence was observed in the National Assembly, where Prime Minister Jean Castex was detailing the nationwide lockdown, which will come into force on Thursday night.
"Without question this is a very serious new challenge that is striking our country," the BBC quoted Castex as saying.
Interior Minister Gerald Darmanin has asked residents to avoid the attack area.
In 2016, Nice witnessed one of France's deadliest attacks in modern history when a 31-year-old Tunisian drove a truck into crowds celebrating Bastille Day, killing 86 people.
Thursday's attack comes after middle-school teacher Samuel Paty was beheaded by an 18-year-old Muslim immigrant, Abdullakh Anzorov inside a school near Paris on October 16.
Source: IANS