A Russian man charged with hacking into U.S. businesses to steal credit card information will try to convince a federal judge on Thursday that his 2014 arrest in the Maldives was illegal and his indictment should be dismissed.

The U.S. Secret Service agents who snatched Roman Seleznev at a Maldives airport plan to testify that their actions were legal.

The agents violated the law when they took him into custody and put him on an airplane, Seleznev's lawyers say. Seleznev is the son of a Russian Parliament member, and Russian authorities condemned the arrest.

Federal prosecutors call Seleznev a leader in the marketplace for stolen credit cards, alleging he hacked into the computer systems of restaurants and businesses and stole about 2 million card numbers.

Seleznev was living an extravagant lifestyle before his arrest, authorities said.

Prosecutors say they have evidence showing he made millions. They say their investigation uncovered two Seleznev bank accounts that received $17.8 million for selling the stolen credit card data.

Prosecutors are expected to argue that Seleznev's 40-count indictment should remain intact and his case should go to trial in May 2016.