WASHINGTON (Reuters) - The U.S. Defense Department awarded Raytheon a $614 million modification for a contract previously valued at $630 million, the Pentagon said in a statement on Monday. Raytheon is tasked with manufacturing 17 missiles, performing support for production and engineering, providing quality assurance, and audit and engineering efforts. Work will be performed in Tucson, Arizona, and is estimated for completion in March 2020, the statement said. 