Hector Xavier Monsegur, of New York, was arrested in June 2011 in secret by the FBI and provided information that led to arrests of other LulzSec members, one American man and four in the U.K. in March. LulzSec was an offshoot of Anonymous, a decentralized group of hackers.

The U.S. Attorney's Office for the Southern District of New York wrote in a letter that Monsegur has continued to help government prosecutors and asked that his sentencing be moved six months ahead. Monsegur was scheduled for sentencing on Wednesday. U.S. District Judge Loretta A. Preska approved the request on Tuesday, according to court documents.

Monsegur pleaded guilty in August 2011 to various hacking charges, including attacks against HBGary Federal, the Public Broadcasting System, Sony Pictures and Fox. It is not clear what kind of plea bargaining arrangement Monsegur secured with prosecutors.

The hacking attacks were part of a months-long hacking campaign waged in 2011 by LulzSec against companies and organizations and publicized through Monsegur's prolific activity on Twitter. Other targets included News International and Booz-Allen Hamilton.