Top Secret Service officials ordered members of a special unit responsible for patrolling the White House perimeter to abandon their posts over at least two months in 2011 in order to protect a personal friend of the agency’s director, according to three people familiar with the operation. The new assignment, known internally as Operation Moonlight, diverted agents to a rural area outside the southern Maryland town of La Plata, nearly an hour’s drive from Washington. Agents were told that then-Director Mark Sullivan was concerned that his assistant was being harassed by her neighbor, the three people said. Two agents were...