Staffers of the U.S. Agency for International Development have been instructed to stay out of its Washington headquarters after billionaire Elon Musk announced that President Donald Trump had agreed with him to shut the agency down. That's according to a notice distributed to the staffers early Monday. Musk, Trump and some Republican lawmakers have targeted the U.S. Aid and Development Agency, which oversees humanitarian, development and security programs in some 120 countries, in increasingly strident terms, accusing it of promoting liberal causes. USAID staffers say they tracked 600 employees who reported being locked out of the agency’s computer systems overnight. Those still in the system received emails saying the headquarters building will be closed to agency personnel on Monday, Feb. 3. The developments come after Musk said he'd spoken with Trump about the U.S. Aid and Development Agency, and the Republican president agreed they should shut it. Democratic lawmakers have protested the moves, saying Trump lacks constitutional authority to shut down USAID without congressional approval.