Police cordoned off the area, including the former Charlie Hebdo offices, after a suspicious package was spotted nearby.
“I was in my office. I heard screams on the road. I looked out the window and saw a woman lying on the ground who had taken a blow to the face from what was possibly a machete, ”a witness told Europe 1 radio. I saw a second neighbor on the ground and went to help.
A Parisian police official said that while authorities initially believed two attackers were involved, they now believe it was just one person.
Paris police have said that a person arrested near the Opera de la Bastille has now been released; his profile did not match the description of a witness. A second suspect was arrested near the Richard Lenoir metro station, which adjoins the former Charlie Hebdo offices.
Police initially announced that four people were injured in the attack, but later confirmed that there were two victims. One would be seriously injured.
Neighboring schools have been locked away, with parents urged not to pick up their children.
The Paris prosecutor’s office has opened an investigation into an “assassination attempt”.
The attack comes three weeks after 14 people suspected of having links to local fighters who attacked the Charlie Hebdo offices in January 2015, killing 12 people, were tried in Paris.
The court heard they had sought revenge on the Prophet Muhammad, nearly a decade after the weekly cartoons published mocking him.
The magazine moved its offices after the 2015 attack.
With reports by Rebecca Rosman in Paris.
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