STRATFORD - The U.S. Defense Department has concerns over the merger of Lockheed Martin with Stratford-based Sikorsky aircraft.

They are worried about the size of the merged company.

Pentagon officials said yesterday that they would work with the Justice Department and Congress to preserve a diverse industrial base.

In response, Lockheed reportedly wrote an email saying, "There is no evidence to support the view that larger defense companies reduce competition or inhibit innovation."