1. A gunman opened fire on a French police vehicle on the famous Champs-Élysées avenue in Paris on Thursday, killing one officer and injuring three others, authorities said.

Christian Hartmann / Reuters

2. “A [police] car parked on the #ChampsElysees was targeted by an individual’s gunfire,” the Ministry of Interior said on Twitter. “The individual was shot dead by law enforcement.”

Franck Fife / AFP / Getty Images

French President François Hollande addressed the nation Thursday night, calling “terrorist in nature” and said the French security forces would be working to investigate the motive and any accomplices who may have played a role.

“We believe the attack is of a terrorist nature,” Hollande said.

French officials have not made any public statement linking the terror group to the shooting. But Site Intel Group, which monitors insurgent networks, said ISIS claimed responsibility for the attack through its news agency, Amaq.

ISIS has claimed responsibility for attacks where the suspects were found to have no direct link to the group. On Thursday, however, the claim of responsibility from the terrorist group came much more quickly than in the past.

The pseudonym listed for the alleged attacker, Abu Yusuf al-Beljiki, suggested he had some sort of tie to the group, the Associated Press reported.

Few details were released overnight about the suspected gunman, other than that he was 39 years old and lived east of Paris, according to the AP.

In his address, Hollande also expressed his condolences for the slain officer and two other officers who were injured in the confrontation.

A bystander was also wounded in the shootout.

“Our security is at stake,” Hollande said. “This is the message I would like to send tonight. This is a message not only to police forces, the army, its a message to everyone: you will be protected.”

France’s Interior Minister Matthias Fekl touted the work of police at the scene, and said their quick avoided more injuries.

“We’ve avoided a bigger tragedy on the Champs-Elysées,” Fekl told reporters. “Tonight, we avoided a bloodbath that could have been extremely dire.”

Ministry spokesman Pierre-Henry Brandet told BFM television that a man exited a car and opened fire on the police vehicle, “deliberately” targeting the officers with an automatic weapon.

There was “no other police operation underway” in the popular shopping district, he said.

Brandet told reporters the shooter’s background and motive had not immediately been determined, but that France remained on high alert because of past terror threats.

Brandet confirmed counterterrorism investigators have been called to look into the shooting, and that the country remains on high alert.

“If this is considered to be a terrorist attack, this is a serious crime and there may be some accomplices to be interrogated,” he said.

Overnight, French Prosecutor Francois Molins said investigators had determined the identity of the gunman, and were conducting searches throughout Paris, the Associated Press reported.

6. Dozens of police cars and helicopters descended on the popular tourist strip following the shooting, with police urging the public to avoid the area.

Thomas Samson / AFP / Getty Images

7. Anti-terror prosecutors had also reportedly mobilized to investigate the incident.

Thomas Samson / AFP / Getty Images

France remains under a state of emergency and security forces have been out in greater force in Paris in the wake of deadly Islamic extremist attacks over the years.

“Tribute to the slain police officer at the Champs-Elysées tonight,” French Prime Minister Bernard Cazeneuve wrote on Twitter. “Solidarity to [the officer’s] injured colleagues and their loved ones.”

While speaking at the White House alongside the Italian prime minister, President Donald Trump offered condolences to the people of France.

“It looks like another terrorist attack,” Trump said. “What can you say? It just never ends. We have to be strong and we have to be vigilant.”

French voters are set to go to the polls on Sunday in the first round of the country’s presidential election.

9. The US State Department, meanwhile, advised people to avoid the area and monitor local news.

“Authorities are telling people to avoid the area after a shooting,” the department tweeted.

This is a developing news story. Check back for updates or follow BuzzFeed News on Twitter.

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