Haiti entered a three-day period of mourning on Tuesday over a fatal stampede that left 25 people dead over the weekend at a historic mountaintop fortress in the north of the country. National police said on Monday they arrested seven people in the town of Milot, at the foot of the citadel, suspected of involvement. Those arrested include five municipal police officers and two National Heritage Preservation Institute staff members. Police said they were held for questioning, without specifying