Gheorgui 'Mitsubishi' Martov, the alleged boss of an organized crime group charged with credit card fraud and money laundering in Chicago has ties to organized crime in Bulgaria.

This claim emerged in a recent US court filing, according to the Chicago Sun.

Martov was arrested in the US along with 15 other Bulgarians in an FBI operation on March 26 and was described as part of a 30-strong crime group dealing with ATM fraud schemes.

Last month the Bulgarian was accused of helping to drain thousands of USD (some USD 200 000 a week) from credit cards by providing numbers of cards stolen in Europe to gang members.

The authorities said his scheme had its headquarters in Sofia, Bulgaria.

The Chicago Sun has described Martov as "a playboy who gambling websites show enjoyed success in high-stakes poker games".

Other details about alleged criminal activity by the crime group's boss have meanwhile emerged. Further court evidence has stated that, back in 2012, he met known leaders of Bulgaria's "underworld" at a Sofia hotel.

Wiretapped calls dating 2011 have also suggested he issues and order that a man owing him money be attacked in Bulgaria and later issued a threat to "cut into pieces" another victim.

In 2012 he told an informant about having kidnapped a person in Chicago and forced him to give back USD 800 000 "stolen from organized crime figures".

Meeting with underworld figures was confirmed by Martov and Radoslav Pavlov, another defendant.

After new evidence purporting a number of other charges against Martov, he will not be freed on bond ahead of the trial.

His attorney Tania Dimitrova said he had not been charged with a violent crime and described the prosecutors' fresh allegations as "completely inaccurate".