Rubio becomes USAID's acting head amid Musk's 'shut down' threat

US Secretary of State Marco Rubio has taken over as acting head of US Agency for International Development (USAID) after billionaire Elon Musk claimed President Donald Trump had agreed to shut down the "criminal" aid agency. This came after USAID staffers were locked out of its headquarters and the White House confirmed plans to merge it into the state department.