HONG KONG - DECEMBER 01: Police advance on pro-democracy protesters at the Admiralty MTR station on December 1, 2014 in Hong Kong. Leaders from the Federation of Students called on fellow protesters to attend a rally and come prepared for escalated action. Protesters were asked  to bring masks, umbrellas and helmets in a bid to move the protests forward after police successfully cleared the Mong Kok protest site earlier this week.  (Photo by Chris McGrath/Getty Images)