Updated at 6:05 p.m. ET

One police officer is dead and two seriously wounded after a shooting on Paris’ famous Champs Elysees, in an incident that left one attacker dead. The assailant reportedly targeted a police vehicle. Authorities say a bystander was also wounded.

ISIS has claimed responsibility for the attack, through the group’s semi-official news agency Amaq, reports the SITE intelligence group.

French President Francois Hollande had already said that the authorities suspect the attack was “of a terrorist nature,” according to a French 24 translation of his news conference Thursday night. He says counterterrorism authorities are investigating.

The shooting comes just days before first-round votes are cast Sunday in France’s closely watched presidential election. At the time of the shooting, all 11 presidential candidates were appearing on television.

One of the candidates, Francois Fillon, has canceled his campaign events on Friday, Reuters reports.

NPR’s Eleanor Beardsley reports from the Champs Elysees that the avenue “has been completely cordoned off.

“People are not allowed on it anymore. Traffic has stopped,” she says. “We just see police cars and vans with flashing lights, helicopters overhead.

“Obviously something has happened,” Eleanor says — but “nobody knows” exactly what.

“We’re three days before a presidential election,” Eleanor says. “The country’s on edge.”

The AP, citing a Paris police spokeswoman, reports that the attacker “targeted police guarding the area near the Franklin Roosevelt subway station Thursday night at the center of the avenue popular with tourists.”

Witness Ogur Yilmaz told Eleanor he was leaving a cafe when he heard “two or three shots” and saw people fleeing.

“I was in a panic, and I ran too,” he said.

Police have not identified a motive in the attack.

France remains under a state of emergency, after a series of deadly terrorist attacks over the past several years.

This is a breaking news story. As often happens in situations like these, some information reported early may turn out to be inaccurate. We’ll move quickly to correct the record and we’ll only point to the best information we have at the time.

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