NEWARK, N.J. (AP) — A military contractor has agreed to pay $4 million to settle an overbilling case.

The U.S. attorney’s office in New Jersey announced the settlement with Mission1st Group on Friday.

The Arlington, Virginia-based company specializes in systems engineering, information technology and telecommunications.

Employees of civilian contractors that support U.S. military forces in Iraq and Afghanistan are entitled to danger pay and hazardous duty pay that enhances their salaries.

Authorities allege that in its contracts with Lockheed Martin and USFalcon, the company billed for the salary enhancements but didn’t pay those enhancements to employees.

The overbilling allegedly occurred for more than four years, through the end of 2011.