According to official information, two people were seriously injured in a knife attack in Paris near the former offices of the satirical magazine Charlie Hebdo.
A suspect was arrested in the nearby Bastille. A second suspect was also reportedly arrested.
The anti-terror police have taken over the investigation.
A security chain has been set up in the 11th arrondissement to the east of Paris. The public was urged to avoid the area.
At the site of the attack near Richard Lenoir Boulevard, a blade known as a machete, or meat cleaver, was recovered.
The arrested suspect was arrested with blood on his clothes, French media reports said.
Initial reports said four people had been injured.
The attack comes as a high-profile trial of 14 people is underway in Paris who are alleged to have assisted two jihadists in carrying out the attack on Charlie Hebdo in 2015, which killed 12 people.
The two wounded were employees of a television production company, one of their colleagues told the AFP news agency.
“Two colleagues were smoking a cigarette in the street in front of the building. I heard shouts. I went to the window and saw one of my bloodied colleagues being followed by a man with a machete in the street,” said another member of the employees of the Premières Lignes production company said.
The company has offices on Rue Nicolas Appert, a side street off Boulevard Richard Lenoir where Charlie Hebdo’s former offices are.
The satirical magazine has now moved to a secret location.