Hong Kong police have detained a prominent pro-democracy activist and at least seven other people on the 34th anniversary of the bloody Tiananmen Square crackdown in China. For years, Hongkongers would converge on the city’s Victoria Park and its surrounding neighbourhood to commemorate the events of 4 June 1989, taking part in candlelight vigils. This weekend, scores of police were deployed in the area, stopping people to search their belongings and question them. By late afternoon, reporters had witnessed at least eight people taken away by police in vans – including Alexandra Wong, a well-known pro-democracy activist better known as...