A rapidly evolving corruption scandal involving alleged attempts by World Cup host Qatar to buy influence at the nerve center of the European Union has ensnared at least three members of the European Parliament and threatens to lay bare a culture of corruption and bureaucratic impunity at one of the EU’s deliberative bodies.

On Sunday a Belgian judge charged four people with “participation in a criminal organization, money laundering and corruption.” The charges came after Belgium’s federal prosecutor said that police seized about $630,000 in cash, computers, and cellphones after searches at 16 locations across Brussels on Friday.

One of the suspects is Eva Kaili, a vice-president of the European Parliament, who has been stripped of her duties in the European legislature and sent to a prison at Brussels pending a pre-trial detention hearing. 

In a statement, the Belgian prosecutor’s office said that “It is suspected that third parties in political and/or strategic positions within the European parliament were paid large sums of money or offered substantial gifts to influence parliament’s decisions.” 

Belgian media identified the country that was trying to buy influence as Qatar. The Financial Times reported Ms. Kaili had defended Qatar’s human rights record just last month in Europe’s parliament and praised the country as “a frontrunner in labor rights.” According to the Guardian, last month Ms. Kaili met with the Qatari labor minister, Ali bin Samikh Al Marri, shortly before the World Cup began.

Ms. Kaili was also expelled from her political party in Greece, Pasok, which is that country’s socialist party. The politician who made the decision to oust her, Nikos Androulakis, is both head of Pasok and a member of the European Parliament, or MEP. The saga of the 44-year-old former television presenter’s arrest and how Belgian authorities reportedly caught her red-handed with bags of cash has dominated headlines in much of Europe

A prominent Greek newspaper, Ta Nea, reported on Monday that another of the suspects is a Belgian MEP, Marc Tarabella. Investigators  said he was not in custody, but the Belgian newspaper Le Soir reported that he was under house arrest. The newspaper reported that another suspect in the investigation was Marie Arena, another Belgian MEP. 

Italian media, meanwhile, have focused on Italian nationals implicated in the unfolding scandal, chief among them Antonio Panzeri, a Brussels lobbyist and former MEP that La Repubblica identified as the mastermind of the operation. The Italian newspaper reported that Mr. Panzeri allegedly had initial contacts with Qataris between 2016 and 2018, and that among Qatar’s aims was the issuance of visa waivers so that Qataris could travel unhindered throughout the European Union.

Greek media reported that among the others detained was Ms. Kaili’s Italian partner, Francesco Giorgi, who was said to be working as a human rights consultant at the European Parliament.

In a statement, the European Commissioner for Economy, Paolo Gentiloni Silveri, said it would be “shameful and intolerable” if “what emerges from the first decisions of the Brussels prosecutor’s office is that representatives of Parliament and activists received bribes to turn a blind eye to working conditions in Qatar.” Mr. Silveri answers to Ursula von der Leyen, president of the European Commission, which is headquartered at Brussels. 

The European Parliament is headquartered at Strasbourg with a presence at Brussels, the unofficial capital of the EU. An Italian MEP not implicated in the current probe, Dino Giarrusso, described to the Financial Times how many lawmakers at Brussels had been approached by Qatari officials: “They were hoping to improve the country’s reputation, especially in the run-up to the Fifa World Cup,” Mr. Giarrusso said. 

While the investigation has only begun, its breadth and scope points to a culture of corruption at Brussels at a time when European unity is already deeply fractured by developments as varied as Brexit and the war in Ukraine.

On Monday the vice president of the European Commission, Josep Borell, told reporters that “Certainly the news is very worrisome, very, very worrisome. We are facing some events, some facts that certainly worry me as a former President of the European Parliament.”

A British correspondent for Deutsche Welle, Jack Parrock, told the Greek television channel ANT1 that “the scandal is only one aspect of the corruption that may be endemic in the European Parliament.” Mr. Parrock said he thought that Ms. Kaili and others “became pawns in the chessboard of the competitions opened in the European Parliament by the Gulf countries.”

Qatar has so far denied any involvement, with one official saying that “any association of the Qatari government with the reported claims is baseless and gravely misinformed.” 

Since Russia’s invasion of Ukraine last February, Brussels has occasionally been described as a den of spies, particularly with respect to Russia and China. Now, as shady dealings of a more financial stripe see the light of day and European lawmakers are staring down possible jail time for taking bribes, the lack of oversight in the power center of the European project may soon  be eclipsed by outrage.

If nothing else, the accelerating pace with which the Belgian authorities are chasing down leads may be a sign that days of a culture of bureaucratic impunity at Brussels are numbered.