Three suspects close to the attacker remain in custody, the Paris prosecutor's office said on Saturday.
The attack, which killed one police officer, could influence voters who will cast their ballots Sunday, analysts say. The gunman carried a note praising the Islamic State group.
Will the French election be the latest in a series of political events to shock the world? The country has seen a series of attacks that have killed almost 240 people in the past two years. Every presidential election since 1965 has gone to a second round.
"By country, faster business activity growth in France - the strongest seen since May 2011 - was offset by a moderation in Germany, albeit with the pace of German expansion still running at one of the fastest seen over the past six years", a release from Markit announcing the data said.
The candidates' proposals show that whatever the outcome this election will not only shape the future of France, but also of the European Union.
A presidential election in France is not usually the sort of thing that I would tell you to pay attention to.
Opinion polls showed a tight race among four top contenders vying for the two places in the May 7 runoff that will decide who becomes the next head of state.
Our country, France, has again known the barbarism of a terrorist attack at the very heart of our capital, she said, as she hit out at France's so-called leaders for failing to protect citizens. "Whoever is the toughest on radical Islamic terrorism, and whoever is the toughest at the borders, will do well in the election".
In a just-published interview with the Associated Press, Donald Trump all but endorsed Marie Le Pen, the ultra-nationalist, Nazi-coddling leader of France's far-right National Front party in the upcoming French elections. Both Le Pen and Mélenchon have said they want to radically renegotiate France's relationship with Europe and could hold referendums on a French exit from the bloc.
Prime Minister Bernard Cazeneuveaccused Le Pen of attempting to make political hay out of the Champs Elysees attack, saying she was "seeking, as she does after every tragedy, to take advantage of it".
Macron is in the lead with 24% of the first-round vote, ahead of Le Pen who had fallen back slightly to 21.5%, according to an Elabe survey of voter intentions taken before the shooting.
Fillon will vote in Paris, but his wife - who's been handed preliminary charges for her role in the fake jobs scandal that rocked her husband's campaign - voted 250 kilometers (155 miles) away near their 14th century manor house in Sarthe. "The fight against terrorism must be the absolute priority of the next French president".
"I think we must one and all have a spirit of responsibility at this extreme time and not give in to panic and not allow it to be exploited, which some might try to do", he told French radio.
The centrist candidate Emmanuel Macron still sits atop most polls, and the conservative Francois Fillon remains within striking distance.
Either way, it's safe to say Macron was extremely happy about the call. "If we're believers in freedom, we must live with it". But a late surge in the polls by a far left candidate, Jean-Luc Melenchon, has raised the prospect that she will be joined by a second eurosceptic candidate.