A former sailor assigned to a US nuclear aircraft carrier and another man have been charged with hacking the computer systems of 30 public and private organizations, including the US Navy, the Department of Homeland Security, AT&T, and Harvard University.

Nicholas Paul Knight, 27, of Chantilly, VA, and Daniel Trenton Krueger, 20, of Salem, IL, were members of a crew that hacked protected computers as part of a scheme to steal personal identities and obstruct justice, according to a criminal complaint unsealed earlier this week in a US District Court in Tulsa, Oklahoma. The gang, which went by the name Team Digi7al, allegedly took to Twitter to boast of the intrusions and publicly disclose sensitive data that was taken. The hacking spree lasted from April 2012 to June 2013, prosecutors said.

At the time of the alleged hacks, Knight was an active duty enlisted member of the Navy assigned to the nuclear aircraft carrier USS Harry S. Truman, prosecutors said. He worked as a systems administrator in the carrier's nuclear reactor department. He is accused of conducting some of his unlawful hacking while aboard. The "self-professed leader of Team Digi7al [and] the primary publicist and Twitter poster," Knight was discharged after trying to hack into a Navy database while at sea, according to court documents. There are no allegations that he hacked any of the carrier's systems. Krueger, meanwhile, was a student studying network administration at an Illinois community college. The two men were allegedly aided by three unnamed minors who were not charged in the complaint.

Among the 30 organizations Team Digi7al targeted was the Navy's "Smart Web Move" database, which contained social security numbers and other personal information for more than 220,000 service members for the purpose of managing duty station transfers. Using a hacking technique known as a SQL injection exploit, Krueger allegedly downloaded the database contents for the purpose of making it public. As a result of the intrusion, the database was shut down and more than 70 overseas service members were unable to receive support for transfers for more than 10 weeks, court documents allege. The Navy spent $514,000 responding to the attack, assessing the damage, paying contractors and employees to repair the damage, and providing credit monitoring and other services to service members whose data was exposed.

Knight and Krueger are charged with a single count of conspiracy to hack computers as part of a plan to steal identities, obstruct justice, and damage a protected computer. They have not yet entered a plea in the case, although Knight recently told ABC News he "did dumb things."