NEW YORK (AP) - A self-described anarchist and hacker activist in the United States (US) pleaded guilty on Tuesday to charges he illegally accessed computer systems of law enforcement agencies and government contractors.
Prosecutors had alleged that Jeremy Hammond took part in cyberattacks carried out by Anonymous, the loosely organised worldwide hacking group that stole confidential information, defaced websites and temporarily put some victims out of business.
Hammond was caught last year with the help of Hector Xavier Monsegur, a famous hacker known as Sabu who later helped law enforcement infiltrate Anonymous.
"For each of these hacks, I knew what I was doing was wrong," Hammond told a judge in federal court in New York City. He faces a maximum sentence of more than 15 years at sentencing on Sept 6.
Secrets-spilling group WikiLeaks published much of the material Hammond is accused of having stolen. Wikileaks chief Julian Assange responded to the guilty plea on Tuesday with a statement saying, "The Obama administration's treatment of Jeremy Hammond is a disgrace".
A criminal complaint had accused Hammond of pilfering information of more than 850,000 people via his attack on Texas-based Strategic Forecasting Inc, a publisher of geopolitical information also known as Stratfor. He also was accused of using the credit card numbers of Stratfor clients to make charges of at least US$700,000 (S$883,000).
Hammond, 28, once rallied against plans to hold the 2016 Olympics in Chicago because he felt it would hurt low-income people; another time, he protested against neo-Nazi groups.
A website for supporters, freehammond.com, has described Hammond as "one of the few true electronic Robin Hoods". But prosecutors called him a menace. Hammond, who used online aliases such as "crediblethreat" and "yohoho", once described himself as "an anarchist communist", the complaint says.
"Jeremy has taken responsibility for what he's done, but he should not face such a harsh sentence for an act of protest from which he did not personally benefit," his brother, Mr Jason Hammond, said in a statement.