Police negotiators say Occupy Central has presented them with their toughest challenge yet, facing hundreds of sometimes hostile demonstrators instead of the one or two people they usually deal with. Some officers worked 24-hour shifts trying to negotiate pathways for emergency vehicles and defuse tensions between frontline police and protesters, often amid a barrage of insults and with little success. "We're not used to facing big crowds like these," said Chan Chi-wai, who is a marine police officer as well as a member of the 62-strong Police Negotiation Cadre. "It's never been like this before," he added. Chan negotiated with the crowds in Mong Kok last week, as well as talking to protesters on Lung Wo Road outside the Chief Executive's Office about letting in food trucks for officers. "The insults just pour in on all sides, but you have to push it aside in order to function and complete the task," he said. Crowd behaviour also hampered officers trying to talk a man out of jumping off a bridge leading to government headquarters in Admiralty. Senior inspector Calvin Cheung Kin-pan, one of the negotiators, said the large number of people at the scene made it extremely hard to control the situation. "People shouted out things, which were so provoking we were very worried [the man] would jump in many instances," Cheung said. "He was so emotional, at one point he was shaking." In the end, the man agreed to climb down after family and friends showed support, and the police were able to calm his emotions to a point where he could think clearly. Explaining the failure to keep a path open for emergency vehicles such as ambulances and fire trucks, detective senior inspector and negotiator Rachel Hui Yee-wai said one of the biggest challenges was finding someone in charge at the locations who was able to make decisions. "We'd often come to an understanding with protesters willing to open up a part of the road, only to have it blocked again by other protesters who disagreed," she said. Hui said many protesters did not understand that the negotiators' job was to get the police message across, and not to discuss politics. The unit's commanding officer, Gilbert Wong Kwong-hing, said the number of negotiators involved and their tactics could not be divulged until the movement had ended.