French authorities have opened an investigation into the far-right National Front (FN) party over an alleged fraudulent use of assistants in the European Parliament.

The investigation was opened on 15 December by judges in Paris who specialise in financial cases, but reported by French media and later confirmed on Thursday (5 January).

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It covers charges of embezzlement, organised fraud, forgery, and undeclared work, following a preliminary investigation that was opened in March 2015 at the request of European Parliament president Martin Schulz.

The parliament had found that 20 people registered as assistants to the 24 National Front MEPs and paid for by the parliament were in fact working for the party at its headquarters in Nanterre, near Paris.

Their names were on the party organisation chart in France, but four of them were listed as "accredited" EU parliament assistants and should have been working in Brussels and Strasbourg. The 16 others were registered as local assistants who were meant to be working in the MEPs’ constituencies.

Recovering money

After discovering the discrepancy, the EU parliament informed the EU anti-fraud office, Olaf, of possible financial irregularities.

Schulz also wrote to the French justice minister to say that he was ready to hand documents to French judges.

"According to the National Front's own organisation chart, certain assistants do not work for the members with whom they have concluded their labour contracts," the parliament said in statement at the time.

Following the Olaf investigation, the European Parliament has so far asked three FN MEPs to pay back salaries unduly paid. In September 2016, for instance, the party's leader Marine Le Pen was asked to repay €339,946 to cover the salaries of two of her assistants.

The money is still to be recovered by the parliament, while Olaf continues its investigation into the other MEPs' assistants.

In June 2015, Le Pen created her own group in the parliament, Europe of Nations and Freedom, with other far-right parties, such as the Netherland's PVV and Austria's FPOe.

On Thursday, Le Pen said that the investigation, coming ahead of presidential and parliamentary elections in France this year, was "a caricature".

"The old political methods of persecuting opponents refuse to die," she told the AFP press agency.

Funding problems

The investigation over the parliament assistants comes after another investigation was opened last year about the funding of Le Pen's campaigns for local elections in 2011 and for legislative elections in 2012. It was recently extended to also cover her earlier presidential bid in 2012.

Judges are looking at how a structure within the National Front overpriced services such as printing leaflets to fund the leader's campaigns

Le Pen is leading in a majority of opinion polls ahead of the presidential election in April and May, although a victory in the run-off is still considered unlikely.

She is struggling to fund her campaign and her party's campaign for the legislative elections in June.

The FN admitted last week that Le Pen's father and party founder Jean-Marie Le Pen would lend €6 million even if he was excluded in 2015 after a political and personal fallout with his daughter.

A few days earlier, the party's treasurer had denied reports that he was trying to contract a €28 million loan from banks in Russia.

In 2014, another bank, the First Czech-Russian Bank lent €9 million to the FN, but it emerged earlier this week that Russia had started legal proceeding to recover the money.