Belgium on Friday detained four people including a former MEP as part of a probe into suspected corruption by "a Gulf country" at the EU parliament, the prosecutor's office said.
It did not designate a specific nation, but Belgian daily Le Soir said Qatari officials attempted to corrupt an Italian Socialist who was a member of the European Parliament from 2004 to 2019.
For several months, investigators "have suspected a Gulf country of influencing the economic and political decisions of the European Parliament, and this by transferring consequential sums of money or giving sizeable gifts to third parties with a significant and/or strategic position within the European Parliament," the prosecutor's office said.
"Among those arrested is a former member of the European Parliament," it said, without providing more details on the identity of those detained.
The investigation was looking into "corruption" and "money laundering".
The police on Friday carried out 16 raids in the Belgian capital, seizing "€600,000 in cash", as well as IT equipment and mobile phones whose content would be examined.