Four people have been wounded in a knife attack near the former Charlie Hebdo offices, Paris police said on Friday. Two assailants are on the run.
A police official said officers are "actively hunting" the perpetrators and have cordoned off the area.
Paris police have told the public to avoid the area and await further instructions.
The French satirical newspaper had republished controversial cartoons of the Prophet Muhammad to mark the start of a trial of suspected accomplices of terrorist gunmen who attacked its offices in January 2015.
Fourteen people are accused of obtaining weapons and providing logistical support for the 2015 Charlie Hebdo attacks. The trial was due to start in March but was delayed by the coronavirus pandemic.
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