Hong Kong police arrested four people and detained five others Tuesday as authorities sought to stamp out commemorations of the 1989 Tiananmen Square crackdown on pro-democracy demonstrators in mainland China on its 35th anniversary. Police were out in force patrolling Hong Kong’s Victoria Park, where an annual candlelight vigil had been held until recent years. As police patrolled the area, including the two closest subway stations, they did not hesitate to take away people who were...