At least one police officer was killed, and the attacker was neutralised in a shooting in Paris on Thursday, according to CNN affiliate BFMTV and the French Interior Ministry.
BFMTV also reports that another police officer was seriously injured and an unidentified man was hit by the "cross-fire" in the the Champs-Elysees area.
BFMTV has not specified if the unidentified man was the attacker or a bystander.
Following the shoot out, the Champs-Elysees has been closed and authorities are telling people to avoid the area.
The shooting comes three days before French General Elections and Paris was already in a state of heightened alert.
The Presidential Palace, the Elysee, is only a few blocks away.
The French Police tweeted, "Police intervention underway in the area of the #ChampsElysees avoid the sector and follow the instructions of the police forces.