French authorities raided five banks in Paris' financial district on 28 March, as part of a huge investigation into a multi-billion euro tax fraud scheme.

The searches come as the global banking sector is in turmoil following this month's collapse in the United States of Silicon Valley Bank and Signature Bank, and the government-orchestrated takeover of Credit Suisse by rival UBS. 

The French National Prosecutor's Office confirmed in a statement on 28 March that the raids on the banks were the result of five preliminary investigations of aggravated tax fraud, originally opened in December 2021.

While prosecutors did not name the targeted banks in their statement, Le Monde identified them as France's Société Générale, BNP Paribas, Exane, Natixis, and HSBC.

The PNF financial prosecution office said in a statement the probe was linked to so-called "cum-ex" dividend stripping, a trading scheme whereby banks and investors swiftly trade shares of companies around their dividend payout day.

As many as 150 finance investigations are now open into the scheme, prosecutors said, with a further 16 French magistrates and six prosecutors out of Cologne, Germany also on the case.