Major defense contractor Northrop Grumman wrongly charged the U.S. government more than $100 million, according to a new report from an internal government watchdog.

From October 2007 through March 2013, the company "did not properly charge labor rates," according to the Department of Defense's inspector general.

Furthermore, the Army agency in charge of the contract failed to make sure its workers had the necessary qualifications, according to the Washington Post.

The report, marked "for official use only," was first obtained by nonprofit Project on Government Oversight.

The IG found $21.7 million in excessive overtime payments, including one employee who billed $177,000 for 1,200 hours in just 12 days.

In addition, only 100 of the 460 DynCorp employees working for Northrop Grumman met specified labor requirements.

DynCorp is a Grumman subcontractor, which supplies spare parts, maintenance and training for the Afghan Defense Ministry, the Afghan Army Air Corps and the Afghanistan Interior Ministry's Counter-Narcotics Air Squadron, according to the Post.

These 360 DynCorp employees charged DOD $91.4 million in questionable costs.

For example, one program manger billed nearly 5,800 hours for 18 months worth of work, costing $1.2 million. This was all done sans a bachelor's degree, one of the position requirements.

“The report makes no mention of sanctions or legal actions against Northrop or DynCorp, aside from seeking a refund for the improper charges,” POGO investigator Neil Gordon wrote in a blog post.

Last month, the Washington Examiner reported DynCorp has raked in more than two-thirds of the $4 billion the State Department has spent rebuilding Afghanistan in recent years.

Read the full article here.