Lockheed Martin Corp. on Monday said that it would acquire QTC Holdings Inc., a Diamond Bar provider of medical diagnostic testing for U.S. government employees.

QTC is considered the largest outsourced provider of medical evaluation services to the federal government and the U.S. Department of Veterans Affairs. It processed more than 450,000 evaluations last year.

“QTC aligns with our IT expertise and adjacent market growth strategy,” Bob Stevens, chief executive of the Bethesda, Md. defense contractor, said in a statement.

Terms of the deal were not disclosed, Pending antitrust review, the deal is expected to close by the end of the year.