The chief executive of a major Polish fintech company has been detained in the U.S. as part of an investigation into a massive loss of customer funds.
The man has been wanted by law enforcement authorities in Poland under a Red Notice issued by Interpol for his role in the alleged fraud case.
His arrest follows the collapse of the largest crypto trading platform in the Polish market, whose bosses are also believed to be hiding abroad.
Cinkciarz CEO faces extradition proceedings in the U.S.
The head of Cinkciarz.pl, a popular online currency exchange in Poland, has been detained in the United States this week, Polish media unveiled.
Identified as Marcin P., the fintech executive was apprehended on Tuesday, May 19, as part of a procedure for extradition to his home country.
The news of his detention was confirmed by the Prosecutor’s Office in Poznań, which leads the Polish probe into the activities of the failed financial firm.
The arrest resulted from a months-long cooperation with U.S. agencies, including the Federal Bureau of Investigation (FBI) and the Department of Justice (DOJ).
What happens next will be decided by a U.S. court, which will review the extradition case and determine future proceedings, Polish prosecutors said through a spokesperson.
What happened with the Cinkciarz exchange?
Cinkciarz was one of the most recognizable names in the Polish fintech space for many years, the Bitcoin.pl crypto news portal noted in a report on Thursday.
Marcin P. founded the “money changer” in 2006, when such platforms were gaining traction during the foreign currency lending boom in Poland at the time.
The business grew significantly, reaching 35 billion złoty of annual revenue. While its main activity was currency exchange, it entered more segments through affiliated firms.
One such entity, Conotoxia, was offering various other financial services. In October 2024, the Polish Financial Supervision Authority (KNF) revoked its payment institution license.
Regulators accused the company of failing to ensure prudent and stable management of its payment services. Its complaint against the KNF decision was later dismissed by a Warsaw court.
Marcin accused of misuse of customer funds
The group’s management is suspected of diverting funds deposited by customers of the Cinkciarz exchange to fund other, less successful ventures.
In July 2025, a district court in Poznan issued a warrant for a 30-day pretrial detention of its CEO. Prosecutors initially accused him of financial damages exceeding 112 million zloty.
The estimate of customer losses was later corrected to 174 million Polish zloty (over $47 million), as announced by the regional Prosecutor’s Office in February 2026.
It was previously revealed that the authorities had received more than 7,000 complaints from clients who lost access to their deposits on Cinkciarz.pl.
Marcin P. has been wanted since last summer, when Polish authorities said the entrepreneur had likely left the country and was hiding abroad, as reported by Cryptopolitan.
Four other individuals, among them former members of the management boards of Cinkciarz.pl and Conotoxia, were detained and charged with fraud, money laundering and organized crime.
Polish fintech and crypto business shaken by crashes
While the group didn’t work with cryptocurrencies, Polish media described its demise as “one of the biggest scandals in Polish fintech.”
The sector was recently stunned by an even bigger crash – that of Zondacrypto, the largest exchange in the Polish market for digital assets.
The coin trading platform halted withdrawals in April amid reports it was experiencing liquidity issues. Its CEO disappeared shortly after denying the company was at the brink of insolvency.
The executive, Przemysław Kral, is reportedly hiding in Dubai, together with the alleged owner, Marian W., while the company’s founder, Sylwester Suszek, has been missing since 2022, presumed dead.
Some 30,000 Polish customers are believed to have lost at least 350 million zloty (over $95 million) as a result of Zonda’s collapse.
The company is in the eye of a political storm in Warsaw over the future of the industry, which is yet to be regulated in line with the latest European rules.
Poland, a leading crypto market in Central and Eastern Europe, has to implement the EU’s Markets in Crypto Assets (MiCA) regulations by July.