Public auditors were unable to trace back to the source the 144,000 euros ($164,000) in funds contributed to the party in 2017 and notified prosecutors about a possible violation, France’s Europe 1 radio said.
Contributions by a single donor cannot exceed 7,500 euros per year. The publication stressed prosecutors were not looking into possible fraud or illicit financing.
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Macron was elected president in May 2017 after winning a runoff against rightwing National Front leader Marine Le Pen. He founded the centrist La Republique En Marche! party a year before the election.
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