Ukrainian authorities have taken action against the criminals involved in the Zeus cybercrime and money-laundering ring, following law- enforcement raids in Britain and the US.
Ukrainian members of the Zeus gang are purported to be key to the ring's technical infrastructure, which involves millions of computers infected with the Trojan program, a sophisticated piece of malicious software used to steal online banking details and transfer money out of victims' accounts.
"There were some involvements overnight in the Ukraine," said Paul Bresson, a spokesman for the U.S. Federal Bureau of Investigation.
Authorities with the Ukraine's Ministry of Internal Affairs could not be immediately reached for comment. The FBI, which participated in Thursday's arrests in the U.S., has scheduled a press conference in Washington for 1 p.m. Friday.
On Thursday federal and local authorities in New York announced charges against 92 people thought to be responsible for a scam involving online attacks against consumers, small businesses and other organizations that resulted in more than US$200 million in stolen money over the past four years.
The U.S. arrests followed raids on Tuesday in the U.K. in which 20 people were arrested. They were charged with money laundering, document fraud and conspiracy.
Many of those arrested in the US and UK were allegedly involved in setting up bank accounts with fake passports under false names in order to receive money transfers from the victims' accounts. Some are accused of withdrawing the money, keeping up to 10 percent themselves and then sending the rest to those leading the Zeus scheme.
(Robert McMillan in San Francisco contributed to this report.)