Four members of an alleged computer hacking ring were charged with stealing more than $100 million worth of software and data — used to train military pilots and related to Microsoft Corp.'s Xbox gaming console — the U.S. Justice Department said Tuesday.

Two of the four — a 28-year-old New Jersey man and a 22-year-old from Canada — pleaded guilty to charges contained in an indictment unsealed earlier in the day, the agency said.

Prosecutors said the ring hacked into the computer networks of Microsoft and some of its partners between January 2011 and March 2014 to steal source code, technical specifications and other information for the Xbox One gaming console, which had not been released at the time of the attacks.

The hackers also stole information about pre-release versions of the "Gears of War 3" and "Call of Duty: Modern Warfare 3" video games, prosecutors said.

The men were also accused of hacking into the networks of the U.S. Army to steal simulator software for the Boeing Apache attack helicopter, the Justice Department said.

The men allegedly obtained access to the computer networks partly by using the stolen user names and passwords of company employees and others.

Sanadodeh Nesheiwat and David Pokora pleaded guilty to charges in Delaware federal court, the Justice Department said.

Nathan Leroux, 20, of Bowie, Maryland, and Austin Alcala, 18, of McCordsville, Indiana, were also charged in an 18-count superseding indictment, the agency said.