Police detain protesters and students (sitting) after they attempted to escape from Hong Kong Polytechnic University campus and from police, in Hung Hom district in Hong Kong on November 18, 2019. - Dozens of Hong Kong protesters escaped a two-day police siege at a campus late November 18 by shimmying down a rope from a bridge to awaiting motorbikes in a dramatic and perilous breakout that followed a renewed warning by Beijing of a possible intervention to end the crisis engulfing the city. (Photo by Ye Aun