One police officer was killed and another wounded today in a shooting on Paris's Champs Elysees, police said just days ahead of France's presidential election.
Cheurfi was detained two months ago after speaking threateningly about the police but released for lack of evidence, according to two police officials, speaking to AP on condition of anonymity.
BFMTV also reports another police officer was seriously injured and an unidentified man was hit by "cross-fire" in the the Champs-Elysées area.
The attacker was shot dead by police, he said.
Security in France is tight with the country's presidential election just three days away.
France has been under a state of emergency since November 2015, when more than 130 people were killed in a single night by coordinated terrorist attacks in Paris.
In Washington, President Trump said the shooting in Paris "looks like another terrorist attack".
Investigators searched a home early Friday in an eastern suburb of Paris believed linked to the attack.
The shooting has not officially been declared a terrorist act but anti-terrorist forces are leading the investigation, French President Francois Hollande said. Francois Fillon, who is the conservative candidate, said he would cancel the campaign events he had been planning for Friday.
The claim of responsibility came unusually swiftly for the group, which has been losing territory in Iraq and Syria.
The Islamic State group claimed responsibility for the fatal shooting in a statement by the jihadists' propaganda agency Amaq. One of the wounded officers was critically injured but is improving, he said.
With some voters doubtful whether the 39-year-old former banker is experienced enough to be head of state, Macron appealed for cool heads.
Meanwhile, following the attack, the presidential candidates have called off their election campaign.
He fled on foot before the driver of the other vehicle and the passenger - a trainee police officer - caught up with him.
A auto pulled up alongside a police bus just before 21:00 (19:00 GMT) and a man got out, opening fire on the bus with an automatic weapon, Interior Ministry spokesman Pierre-Henry Brandet said.
With polls indicating a record number of voters remain undecided, analysts say the shooting could play into the narrative pushed by the far-right.
After Le Pen spoke scathingly Friday of the government's fight against extremism, Cazeneuve noted that Le Pen's party in 2014 voted against an anti-terrorism law and, in 2015, against a law that beefed up resources for French intelligence services.
German Chancellor Angela Merkel expressed her condolences to Hollande and said her sympathy "goes out to the victims and their families", according to her spokesman Steffen Seibert. The shooter opened fire with an automatic weapon on a police auto on the world-famous boulevard at around 9:00 pm (local time) yesterday, prompting tourists and visitors to run for their lives.
The attack appeared to fit in a spreading pattern of French extremists targeting security forces and symbols of the state, to discredit, take vengeance and destabilize.
3 Feb 2017 - A machete-wielding Egyptian man shouting "Allahu akbar" attacks French soldiers at Paris's Louvre Museum - he is shot and wounded.
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