One police officer was killed and two others were injured in a shooting on the famous Champs-Elysees boulevard on Thursday night in central Paris, stirring security concerns in the days leading up to France's presidential election on Sunday.
The assailant, who fired at officers with a machine gun, was shot dead by police while trying to flee.
The Islamic State group quickly claimed responsibility for the attack through its Amaq news agency, but investigations by authorities are still underway.
The French government is treating the attack as an act of terrorism.
"We are convinced that the leads that are contributing to the investigation, which should reveal the truth, are terrorist in nature."
The shooting unfolded as all 11 presidential contenders were being interviewed on state television.
The incident comes just three days before the first round of voting in the election on Sunday.
France is still under a state of emergency, following the Paris attacks in 2015 that left 130 dead.
Earlier this week, two men were arrested in Marseille for planning an attack ahead of the election.
The latest incident could bring campaigning to an abrupt end one day earlier than planned.
Some presidential candidates are clashing over whether campaigning should be brought to a full stop,
while others have already ended their campaigns early as a show of respect.
Park Se-young, Arirang News.