The raid took place as part of an ongoing investigation into alleged financial irregularities and improper conduct against LEN officials, as reported by State of Swimming.

The LEN’s senior executives at the time of the alleged events are current President Paolo Barelli, also head of the Italian Swimming Federation, current general secretary David Sparkes, also the former chief executive of British Swimming, and former treasurer Tamás Gyárfás, who is also a former head of the Hungarian Swimming Federation.

The LEN leadership has previously denied any wrongdoing in connection to the allegations and an LEN spokesman told insidethegames the accusations were "false."

"LEN has expected the authorities requesting information and documents earlier as it is part of the normal procedure," a spokesman said.

"LEN’s legal team wishes to have the case processed as fast as possible in order to initiate legal actions to those who committed the real wrongdoing against LEN by making false accusations."

It is understood that an investigation against the LEN senior executives was launched by Swiss prosecutors after a former head of Swiss Swimming Bartolo Consolo shared concerns with fellow Board members.

Consolo reportedly shared concerns with prosecutors in Switzerland and Italy and sports ethics panels, including FINA’s own ethics panel.

The allegations centre around claims that so-called "consultancy" companies, some of which were closely associated with Barelli, Sparkes and Gyárfás, received a percentage of broadcast revenue for helping to secure the LEN an increase in fees.

Barelli was last year re-elected LEN President after defeating France's Gilles Sezionale by 86 votes to 13, while Sparkes also retained his general secretary position.

Gyárfás, who was arrested in 2018 on suspicion of ordering the murder of a business rival in 1998, a claim he denies, was replaced as LEN treasurer by Fernando Carpena.