PARIS (Reuters) - Investigators have raided the headquarters of a medical insurance group in western France, local media reported, part of a probe into the financial dealings of one of President Emmanuel Macron’s closest allies days before a parliamentary election.

FILE PHOTO: Emmanuel Macron, head of the political movement En Marche !, or Onwards !, and candidate for the 2017 French presidential election, attends a ceremony at a monument in memory of mass killings of Armenians by Ottoman forces in 1915, in Paris, France, April 24, 2017. REUTERS/Christian Hartmann/File Photo

The investigation is embarrassing for Macron who has put political probity front and center of his first weeks in power, ahead of legislative elections where Macron hopes his new party will win control of parliament and cement his grip on power.

The search was carried out on Thursday after the public prosecutor in Brest launched a preliminary investigation into allegations against Richard Ferrand, focused on his management of Mutuelles de Bretagne, regional daily Telegramme reported on Tuesday.

The allegations include renting office space from his partner and hiring his son as an assistant paid from parliamentary funds.

Ferrand, who was Macron’s campaign chief and is now a cabinet minister, has denied wrongdoing. He has the backing of Prime Minister Edouard Philippe, who has said Ferrand’s actions might raise moral questions but not judicial ones and that he sees no reason to ask him to resign.

Hiring family members as parliamentary assistants is not illegal in France but is increasingly scorned upon by the public.

Last week Justice Minister Francois Bayrou presented to cabinet a draft ethics law aimed at cleaning up politics in France.

“With this law in place, such a thing would not happen,” Bayrou told BFM TV on Tuesday. “The idea to change the way people behave in public life was a pillar of Macron’s campaign.”

Opinion polls show LREM is on course to win a majority in the National Assembly and that the Ferrand affair has not impacted voter intentions.

In France, the opening of a preliminary inquiry does not imply guilt. Prosecutors decide after such preliminary checks whether there are grounds for a full-scale probe or not.