At least two people were stabbed in Paris on Friday (September 25) near the former offices of Charlie Hebdo magazine.
The same offices that were attacked five years ago by Islamist militants.
Police said one person was arrested, and local radio reported a second suspect was in custody.
Media also quoted officials as saying the suspect was 18 and known to security services.
A police source claimed a machete had been found at the scene, while another said a meat cleaver had been found there.
A large security presence soon formed around the area and anti-terror police said they are investigating the incident.
Soon after the stabbings, Prime Minister Jean Castex and Paris Mayor Anne Hidalgo inspected the scene.
Castex said the two people who had been stabbed were journalists having a smoke in the street near the building, and that their lives were not in danger.
The attack comes in the middle of a court trial for 14 people accused of being accomplices in 2015 Charlie Hebdo attack, which killed 12 people.
The court has heard they wanted to avenge the Prophet Mohammed, almost a decade after the satirical magazine published cartoons mocking him.
Security has been on high alert around the trial.
This week, police moved Charlie Hebdo's head of Human Resources from her home after threats were made against her life.