A 20-year-old man was arrested on Wednesday for allegedly breaking into two computers owned by NASA's Jet Propulsion Laboratory and using one to host Internet chat rooms devoted to hacking.

Raymond Torricelli of New Rochelle, New York, was named in a five-count complaint that also charged him with sending unsolicited advertisements for a pornographic Web site and intercepting passwords and usernames traversing networks of computers owned by Georgia Southern University and San Jose State University. He was also accused of stealing credit card numbers that were used to make more than $10,000 in unauthorized purchases. Court papers, which were unsealed in Manhattan federal court, alleged Torricelli was the head of a hacker group known as "#conflict" and that he used the name "rolex." According to the complaint, Torricelli used his home computer in 1998 to break into the two NASA computers at the Jet Propulsion Laboratory in Pasadena, California. Court papers alleged NASA spent several thousand dollars to remedy the intrusions. One of the computers is used by NASA to perform satellite design and mission analysis for future space missions. The other is used by the laboratory's communications ground system section as an e-mail and internal Web server. Torricelli allegedly installed a program on the first computer that enabled him, under his alias "rolex," to hold chat-rooom discussions with other members of "#conflict." Torricelli allegedly used his computer to gain unauthorized access to more than 800 computers, according to the complaint. The defendant also allegedly earned more than $5,200 from an unidentified entity for using these computers to send out unsolicited ads for a pornographic Web site in a practice known as "spamming." Investigators also allegedly found more than 100 stolen credit card numbers on Torricelli's computer. The complaint said American Express , Visa, MasterCard and Discover reported that the authorized cardholders had reported more than $10,000 worth of fraud.