The attacks were claimed by Daesh, which is mainly active in Syria and Iraq.
The Islamic State claimed that it had carried out Thursday's attack on the Champs-Elysees.
A police union on Twitter said the officer who was killed had been shot by an attacker driving past as the officer was auto stopped at a red light.
Hollande says has convened a National Defense and Security Council to meet on Friday morning.
The council comprises top security, police and military figures and several members of the government.
"A man got out of the vehicle and opened fire on the van with an automatic weapon, fatally wounding a policeman". According to the Guardian, there were at least two attackers involved, and one is dead.
Brandet refused to give any specific detail about the suspect's possible criminal history or affiliations.
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The island and castle was the long-time home to House Targaryen, but after Robert's Rebellion it became Stannis Baratheon's home. But where are they? I took the liberty of captioning each photo with the thoughts that went through my head upon seeing them.
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The French interior ministry spokesman said at around midnight that no information circulating concerning the attacker's identity had been confirmed. They had no other details about him. He was shot to death after opening fire on a police van.
The French prosecutors' office said the counter-terrorism office had opened an inquiry. In 2015, six officers were killed by gunfire.
Police union spokesperson Yves Lefebvre from Unité SGP Police said officers were raiding the suspect's residence in Chelles, Seine-et-Marne.
The shooting happened as the country is under a state of emergency from a series of extremist attacks.
"I was in a panic, and I ran too", he said.
"They were running, running", said 55-year-old Badi Ftaïti, who lives in the area. "There were tens, maybe even hundreds of them".
Prior to the Thursday incident, observers had warned that potential terrorist attacks would play well into her hands. "It just never ends". He says people must be strong and vigilant.
Police and soldiers sealed off the area, ordering tourists back into hotels and blocking people from approaching the scene. "Authorities are telling people to avoid the area after a shooting".
French police said that the attack was probably a "terrorist act" and the world famous Champs Elysees was on lockdown by 9pm.
Ministry spokesman Pierre-Henry Brandet said on BFM television that a man came out of a auto and opened fire on a police vehicle.
One officer was killed and another was wounded.
CNN's Paris bureau is witnessing a large police operation in the area.
The shooting comes a matter of days before the first round of the French presidential election, which is taking place on April 23. Earlier this week, police in Marseille arrested two men who were allegedly plotting an attack before the election, per Reuters. The shooting started during the last TV show with all 11 presidential candidates before the first round of the election on Sunday.