Hacker Ringleader Cooperated With Feds from Day 1

An elite computer hacker who stunned fellow Internet saboteurs by becoming an FBI informant didn't put up any resistance when agents first knocked on his door.

Court papers made public Thursday reveal that Hector Xavier Monsegur began cooperating with investigators immediately.

FBI agents arrested him at 10:15 p.m. on June 7. By the next day, federal prosecutors had told a judge that Monsegur had given them "detailed information" on other hackers.

Over the next few months he worked around the clock with agents to identify cyber-attacks before they happened.

Prosecutors said that by August, he had worked with the FBI to "patch" 150 vulnerabilities in computer systems being eyed by hackers.

Monsegur's cooperation led to criminal charges being filed against five other hackers this week.