Port Au Prince — Doctors Without Borders said on Tuesday that it is stopping operations across the Haitian capital, Port-au-Prince, and its wider metropolitan area because of an escalation in violence and threats to its staff from members of the Haitian police. The suspension would begin Wednesday and last “until further notice,” Doctors Without Borders — also known as MSF — said. MSF said in a statement that since a deadly attack on one of its ambulances last week, police had repeatedly stopped its vehicles and directly threatened their staff, some with death or rape. “We are used to working