Lockheed Martin's stock tumbles, wiping nearly $2 billion off its market value

Donald Trump has widened his attack on defense contractors, slamming Lockheed Martin Corp's F-35 fighter jet program as too expensive as aides to the president-elect said he intends to keep pushing to cut the costs of military hardware.

Trump's latest tweet sent defense shares tumbling and fanned concerns that the incoming administration will reduce defense contractors' profit margins and cut broader federal spending, threatening US factory jobs even as Trump promises to boost manufacturing employment.