US Secretary of State Hillary Clinton was due to land in Port au Prince on Saturday to meet with President Rene Preval, who himself has been rendered homeless by the tremor. The Haitian government has handed over control of its airport to the US military, which has landed 1,000 troops into the country already and will bring another 9,000 in coming days to supervise aid deliveries and ensure stability. Some US soldiers had to keep large crowds at bay outside the airport, where some aid supplies have now got stuck because of the difficulties of transporting them into the disaster zone. Doctors at some of the few functioning field clinics complained that they had already run out of medicines.