Geoffroy Van Der Hasselt, AFP | French presidential election candidate for the En Marche ! movement, Emmanuel Macron delivers a speech during a campaign rally on May 1, 2017 at the Paris Event Center.

The French prosecutor’s office, acting on a complaint from presidential contender Emmanuel Macron, opened an investigation on suspicion that fake news had been circulated with the aim of influencing voting in the election, a judicial source said.

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Earlier on Thursday, Macron lodged a legal complaint with the prosecutor’s office over allegations, referred to by his rival Marine Le Pen in a televised debate on Wednesday night, that he held an offshore account.

Macron, the favourite to win the presidency, denied allegations of using a foreign tax haven that were made on social media and referred to by Le Pen in an ill-tempered televised debate with him on Wednesday night. He accused her of spreading lies.

After Macron lodged a legal complaint over the allegations, a judicial source said the prosecutor's office was investigating suspicions that fake news had been intentionally circulated with the aim of swaying Sunday's voting.

Opinion polls show Macron, a centrist, has roughly a 20 point lead over Le Pen. They see him firmly on course to win after what was widely seen as his solid performance in Wednesday evening's fractious face-to-face.

French shares and bonds and the euro performed strongly on Thursday, pointing to relief on financial markets that Le Pen had not gained ground with her pledges to quit the euro currency, hold a referendum on leaving the European Union, and print money to finance higher state spending.

It was at the end of the two-and-a-half hour debate, watched by 15 million people, that the National Front veteran insinuated that Macron might be concealing funds on a foreign tax account.

"I've never had an account in any tax haven," Macron told France Inter radio on Thursday. "Le Pen is behind this. She has an internet army mobilising."

He said she had allies spreading "false information and lies" who were "in certain cases linked to Russian interests".

Macron's party has previously complained that his campaign had been the target of "fake news" put out by Russian media, as well as internet attacks on its databases.

That prompted a warning by the French government in February that it would not accept interference by Russia or any other state in the election.

According to a snap poll by Elabe for BFMTV, 63 percent of viewers found Macron the more convincing of the two candidates in Wednesday's debate, reinforcing his status as favourite to win the Elysee.

A second poll by Harris Interactive said 42 percent of people found Macron more convincing in the debate, during which the candidates traded barbs over the economy, the euro and how to combat terrorism.

Twenty-six percent found Le Pen more convincing, while 31 percent chose neither candidate, Harris said.

An OpinionWay survey carried out before the debate showed Macron widening his lead over Le Pen to 61 percent to 39.

Le Pen's proposal to bring back the franc while replacing the euro with another, looser type of cooperation in the form of an ECU basket of currencies prompted an unusual foray into politics by French central bank governor Francois Villeroy de Galhau.

"I hear proposals for a dual currency with the return of a national currency in parallel to a European currency. I must say that such suggestions would put confidence in the currency in danger," he said at a conference.

A small group of protesters threw eggs at Le Pen as she arrived for a campaign event in Brittany on Thursday, shouting "Out with the Fascists!"

Former U.S. President Barack Obama endorsed Macron in a video message released by Macron's party on Thursday, praising him for appealing "to people's hopes and not their fears".

Campaigning on an anti-EU, anti-globalisation platform, Le Pen has sought to portray Macron, a former investment banker and economy minister, as an out-of-touch member of an elite responsible for France's ills, including unemployment of about 10 percent, low growth and a two-year spate of Islamist violence.

Macron has promised to stimulate growth with training programmes and a relaxation of labour laws, while reducing state expenditure.

Critical father

Le Pen's father Jean-Marie Le Pen was critical of his daughter's performance, saying most viewers would probably have found the first part of the debate incomprehensible.

"That may have benefited Emmanuel Macron, but it didn't work to the advantage of Marine Le Pen, who perhaps lacked gravitas," the founder of the National Front told RTL radio.

By law, official campaigning must end at midnight on Friday before voters go to the polls on Sunday.

Macron's camp said that, two hours before the debate started, an anonymous account posted documents on an Internet forum purporting to prove that Macron had an offshore account, and the information was quickly distributed on Twitter.

Macron's team released a screenshot of what it said was a falsified signature on documents purportedly proving "Macron's secret tax evasion" as well as a trail of tweets spreading the information.

Le Pen told BFM TV on Thursday that she had no proof Macron had an offshore account, but did not want undisclosed funds to come to light when it was too late.

Macron's team say his En Marche! party has been the target of attempts to steal email credentials since January.

Feike Hacquebord, a researcher with security firm Trend Micro, said last week that he had found evidence that it had been targeted by a cyber espionage group linked by some experts to the Russian military intelligence agency GRU.

Russia has denied involvement in attacks on Macron's campaign.

>>Read more on FRANCE24.com: "French presidential hopeful Macron bans Russian-state media from campaign trail"

(REUTERS)

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