San Diego County has become part of the focus of an investigation into a series of retaliatory cyber attack related to the controversy over the WikiLeaks website.Amazon.com and websites for Mastercard, Visa, and PayPal were targeted in recent cyber attacks after Amazon stopped hosting the WikiLeaks site and PayPal refused to handle donations to the organization. WikiLeaks and its founder, Julian Assange, have garnered a lot of media attention recently because of the thousands of classified U.S. documents published on the site.Over the weekend, the FBI executed 40 search warrants across the country on suspected WikiLeaks sympathizers involved in the recent website attacks. 10News learned one of those search warrants was executed in San Diego County."People hide themselves quite well," said professor Murray Jennex, who teaches information systems security at San Diego State University.Computer experts like Jennex said tracing the hackers is a formidable challenge because of so-called "zombie computers."Any computer that has downloaded malicious software can be turned into a zombie computer.When asked how likely it is that San Diegans' computers unknowingly became involved in the website attacks, Jennex answered, "There's a good chance."Jennex said WikiLeaks supporters used thousands of zombie computers in the website attacks. He said the zombie computers flooded company servers with Internet traffic in an effort to shut down the sites.Companies such as Amazon.com can lose millions of dollars when their website is down for just one hour. According to Jennex, it's a big contrast to the amount of resources needed to mount the attack."It's probably a couple people at Starbucks... controlling it from [a] laptop or maybe an iPhone," he said.In the past week, five young men have been arrested in the United Kingdom in connection with the attack.The recent FBI raids in the United States have not yet resulted in any arrests.