American military helicopters landed near the home of Haiti's president Tuesday to deploy troops and supplies in the capital, Port-au-Prince. One group of soldiers was sent to secure the city's main hospital. Medical workers there have been working to treat the many people who were injured in last week's earthquake. Officials estimate that the earthquake killed about two hundred thousand people. Also Tuesday, the United Nations Security Council agreed to add two thousand troops and one thousand five hundred more police to the U.N. forces already in Haiti. The U.N.'s peacekeeping chief said the extra troops will be used to protect vehicles transporting humanitarian supplies.