"This investigation has broken the back of one of the most sophisticated computer hacking rings in the world," said acting US attorney Sally Quillian Yates of the Northern District of Georgia.

Sergei Tsurikov, 25, of Tallinn, Estonia, Viktor Pleshchuk, 28, of St. Petersburg, Russia, and Oleg Covelin, 28, of Chisinau, Moldova, have been indicted by a federal grand jury in Atlanta, Georgia, the department said.

It said a fourth person known only as "Hacker 3" was also indicted on charges of hacking into a computer network operated by Atlanta-based credit card processing company RBS WorldPay, part of the Royal Bank of Scotland.

Tsurikov, Pleshchuk, Covelin and "Hacker 3" were charged with conspiracy to commit wire fraud, wire fraud, conspiracy to commit computer fraud, computer fraud, access device fraud and aggravated identity theft.

They were accused of compromising the data encryption on payroll debit cards, which are used by some companies to allow employees to withdraw their salaries directly from a cash dispenser, or ATM.

Four other residents of Tallinn -- Igor Grudijev, 31, Ronald Tsoi, 31, Evelin Tsoi, 20, and Mihhail Jevgenov, 33, -- were indicted for access device fraud, the Justice Department said.

It said a network of "cashers" were provided with 44 counterfeit payroll debit cards which were used to withdraw nine million dollars from more than 2,100 ATMs in at least 280 cities worldwide, including cities in the United States, Russia, Ukraine, Estonia, Italy, Hong Kong, Japan and Canada.

The nine million dollars was withdrawn within less than 12 hours in November of last year.

The Justice Department said the "cashers" were allowed to keep 30 to 50 percent of the stolen funds, but sent the rest to Tsurikov and the others.

It said Tsurikov, Ronald Tsoi, Evelin Tsoi and Jevgenov were arrested by Estonian authorities earlier this year and face related charges in Estonia.

Tsurikov is facing extradition to the United States where he could face a maximum sentence of up to 20 years in prison for conspiracy to commit wire fraud and up to five years in prison for conspiracy to commit computer fraud.

The Justice Department said two unidentified individuals responsible for withdrawing funds from ATMs in Hong Kong were also arrested by Hong Kong police.

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