Champs-Élysées attacker was known to French police

The attack on one’s of the world’s most famous boulevards came just three days before France goes to the polls Sunday in a hotly contested first round of the 2017 presidential election.

Speaking to reporters near the scene of the attack later Thursday, French prosecutor François Molins said, “The identity of the attacker is known and has been verified.”

But French authorities have declined to provide details of the attacker, who was armed with an automatic rifle.

The gunman, identified as a 39-year-old French man, was known to anti-terror police, sources told AFP.

He was convicted in 2005 on three counts of attempted murder, with two of these against police officers, sources said. The suspect was arrested again in February on suspicion of plotting to kill officers but released due to lack of evidence.

A statement from the Islamic State (IS) group published by its propaganda agency Amaq said the attacker was "one of the Islamic State's fighters".

The Amaq statement identified the attacker as Abu Yussef al-Balgiki, explained Wassim Nasr, FRANCE 24’s expert on jihadist groups. The IS group is known to use noms de guerre, which identify the nationality of the attacker or the “brigade” to which they belong. The term “Balgiki” suggested the attacker either resided or spent time in Belgium, noted Nasr in a Twitter post.

However the Belgian prosecutor on Friday said there was no indication the attacker was Belgian.

Raids took place at his address in the quiet, middle-class suburb of Chelles in the department of Seine-et-Marne, east of Paris.

French police on Friday were hunting a new suspect in connection with the shooting, according to a French interior ministry spokesman.

The second suspect was identified by Belgian security officials and flagged to French authorities, French Interior Ministry spokesman Pierre-Henry Brandet told Europe 1 Friday morning.

The IS group could have named the wrong fighter as Abu Yussef al-Balgiki, meaning the latter could be free, Nasr noted in a Twitter post.

On Thursday night, the attacker opened fire with an automatic weapon on a police van on the iconic boulevard in the heart of the capital at around 9pm local time, prompting tourists and visitors to run for their lives.

Man flagged by Belgian authorities turns himself in

A terror suspect sought by France in the wake of the Champs-Élysées attack turned himself in to Belgian police, France's interior ministry said Friday.

"The man on the wanted notice issued by Belgian authorities presented himself to a police station in Antwerp," ministry spokesman Pierre-Henry Brandet told AFP.

A day after the attack, France held an emergency meeting of top security officials as security was tightened ahead of Sunday’s vote.

French Prime Minister Bernard Cazeneuve said all elite units were on high alert for the election, backing up the 50,000 police already earmarked for special election duty.

"The government is fully mobilised. Nothing must be allowed to impede the fundamental democratic process of our country. It falls to us not to give in to fear and intimidation and manipulation, which would play into the hands of the enemy," said Cazeneuve in a statement released after the emergency meeting.

All eyes on Sunday’s election

Observers had long feared bloodshed ahead of the vote following a string of attacks since 2015 and the violence is likely to thrust security to the forefront of the list of issues concerning voters.

The attack occurred while the 11 candidates contesting the first round were participating in the final TV debate before Sunday's vote.

Three of the main candidates -- far-right candidate Marine Le Pen, her centrist rival Emmanuel Macron, and scandal-hit conservative François Fillon – immediately cancelled campaign events planned for Friday.

Surveys so far have shown voters more concerned about unemployment and their spending power than terrorism or security, though analysts warned this could change in the event of further violence.

However, the French public is no stranger to terror attacks and it is unclear how many would alter their voting decisions based on Thursday’s attack.

French President François Hollande promised "absolute vigilance, particularly with regard to the electoral process" and paid tribute to the police.

Hollande, who said he was convinced the shooting was a "terrorist act", cancelled a trip to the northwestern region of Brittany and will chair a security cabinet meeting on Friday.