The Justice Department on Wednesday released new details in its lawsuit against one of the government’s top background-check firms, alleging that the company filed more than 660,000 flawed investigations of U.S. government hires over four years.

A filing in U.S. District Court in Alabama accuses US Investigations Services, which handles 45 percent of the government’s screening of new hires, of submitting incomplete reviews while collecting $12 million in performance bonuses.

MORE: Justice Department says USIS submitted 665,000 incomplete background checks

A Washington Post report in October first revealed that the Justice Department was joining the civil suit against USIS.

The Washington Navy Yard. (REUTERS/Jason Reed). The Washington Navy Yard. (Jason Reed/Reuters).

USIS conducted background checks for former National Security Agency contractor Edward Snowden, who leaked sensitive information about U.S. surveillance programs, and government contractor Aaron Alexis, who shot and killed 12 people at the Washington Navy Yard last fall.

There is no evidence that the company is accused of submitting incomplete reviews in its investigations of those individuals, according to The Wall Street Journal, which reported the new details in the lawsuit on Wednesday.

USIS said Thursday that the alleged conduct in the lawsuit runs contrary to the firm’s values and commitment to service.

“These allegations relate to a small group of individuals over a specific time period and are inconsistent with the strong service record we have earned since our inception in 1996,” the company said in a statement. “Since first learning of these allegations nearly two years ago, we have acted decisively to reinforce our processes and management to ensure the quality of our work and adherence to OPM requirements. We appointed a new leadership team, enhanced oversight procedures, and improved control protocols.”

Follow Josh Hicks on TwitterFacebook or Google+. Connect by e-mail at  josh.hicks@washpost.comVisit The Federal Eye, The Fed Page and Post Politics for more federal news. E-mail with news tips and other suggestion.