Albert Gonzalez, the computer hacker behind one of the largest known identity fraud cases in US history, was sentenced on Thursday to 20 years in federal prison.

Gonzalez, a 28-year-old college dropout and Secret Service informant known as "soupnazi", had confessed to stealing millions of credit card and debit card numbers from major US retail chains, including TJ Maxx, BJ's Wholesale Club, and Barnes & Noble.

In August 2008, prosecutors accused Gonzalez, along with 10 others from the US, Eastern Europe, and China, of breaking into retail credit card payment systems by 'wardriving' - that is, using a laptop to detect retailers' unsecured wireless networks - and installing sniffer programs to capture data.