After the 1989 military crackdown on protests in Tiananmen Square, many activists were arrested. Some escaped to Hong Kong using an “underground railroad”. The three-storey building in Sai Kung's Nai Chung was one of the biggest shelters that “Operation Yellow Bird” operated for activists as they awaited political asylum in western countries. The man who was one of the key facilitators of the operation and only wants to be identified by his pseudonym “Tiger” takes the Post to the site of the previous Nai Chung camp and reveals details of the operation. Read the full story here.