A second man has been arrested in connection with this week's knife attack in a Nice church in which three people were killed, the French news agency AFP reported, citing judicial sources.
The 35-year-old, who was appreheded in Nice late Friday, is suspected of having been with another suspect the day before the attack.
That suspect is a 47-year-old man was arrested earlier in connection with the Nice church knife attack, and is being held for questioning, acording to French judicial sources.
France's national defence council has spoken of a "terrorist, Islamist attack."
Brahim Aouissaoui, a Tunisian man who entered France illegally on Thursday killed three people in Nice with a knife, according to investigators; two victims were found in the Notre-Dame church in the city centre.
The attacker was seriously injured by the police and was taken to a hospital.
He had only entered France from Italy shortly before the crime.
Highest terror threat level
France declared the highest terror warning level after the attack.
The attack came two weeks after a suspected Islamist beheaded a schoolteacher in a Paris suburb who had shown cartoons of the prophet Mohammed in a lesson on freedom of expression.
The French government's plans for a broad crackdown on Islamism and its fierce defence of the freedom to engage in blasphemy have sparked an angry reaction in many Muslim countries.