"Our prayers are with the family of the police officer who has been killed", he said.
Officers searched the home of the dead attacker in a suburban town east of Paris, according to sources.
The shooting comes three days before French General Elections and Paris was already in a state of heightened alert.
"Our condolences to our country and the people of France".
SHAPIRO: And as we've said, ISIS claimed responsibility for the attack.
Based on current polling, Le Pen is expected to face Center-Right candidate Emmanuel Macron in a runoff in May. Under French election rules, Friday was due to be the final day of campaigning before Sunday's first round of voting.
Said by polls to be running neck-and-neck with Le Pen, he tore into her claims that previous attacks wouldn't have happened under her watch. A staunch isolationist, Le Pen has gained traction among the French electorate for her desire to secure France's borders. "We also have to be clear that we are in a state of emergency". We are at war.
The warning was circulated more widely among French security services in the hour following the Champs Elysees attack. In a statement from its Amaq news agency, the group gave a pseudonym for the shooter, Abu Yusuf al-Beljiki, indicating he was Belgian.
Le Pen has said: "We need to expel the foreign imams who preach the hate and fundamentalism of foreign Fiches S".
Hollande said he convened a meeting of France's defense council for Friday morning.
Around 9 p.m. Paris time (3 p.m. eastern) gunshots were heard around a Marks & Spencer store on Champs-Elysees in central Paris, prompting passersby and tourists to flee the area in panic. The shooter got out of his vehicle and started firing at police, Brandet said on BFMTV.
He fired twice, seriously wounding both men in the chest. This attack had claimed 130 lives and had left 368 others wounded.
The Paris prosecutor's office leading the investigation has said a pump-action shotgun and knives were found in the gunman's vehicle.
He said: "She seems to be deliberately forgetting everything that has been done over five years to make people forget that she opposed everything, without ever proposing anything serious or credible".
Macron said he canceled campaign stops out of a sense of "decency" and to allow police to concentrate their resources on the attack investigation.
Police shot and killed the gunman after he opened fire on a police van on Paris' most famous boulevard on Thursday night. He was taken into custody but while being questioned grabbed another officer's gun and shot him three times, the source added. He was convicted in that attack and had a criminal record because of involvement in violent robberies.
Earlier this week French authorities arrested two men in Marseille who were allegedly planning an attack in a run-up to the election.
Trump himself weighed in at a news conference in Washington following the attack. And what can you say? It just never ends.
"I just want to go home", she said.
British Prime Minister Theresa May also spoke to Hollande. But it looks like another terrorist attack.
France has lived under a state of emergency since 2015 and has suffered a spate of Islamist militant attacks mostly perpetrated by young men who grew up in France and Belgium and that have killed more than 230 people in the past two years.