applied for permits from the police. Security and emergency A total of 9,000 officers from the Hong Kong Police Force were on stand-by for the conference, which was one-third of the regular police force and the greatest number of all the activities the police force has ever been involved in. Officers underwent riot control and shield training. Some of them were sent to observe security arrangements for the Asia-Pacific Economic Cooperation forum summit in Pusan, South Korea. The Commissioner of Police, Dick Lee provided reassurances that weapons such as water cannons and plastic bullets would not be used. Given the police's experience in dealing with previous riots, such as those involving Vietnamese refugees in the 1990s, Mr Lee said the Hong Kong Police Force should be able to handle any protests. In the unlikely event of an emergency which the police cannot handle, the Chief Executive had the power to seek help from the Hong Kong detachment of the People's Liberation Army (PLA). Provisions for this were in the Hong Kong Basic Law. On 17 December, the Hong Kong Police Force used tear gas, pepper spray and fire hoses in order to suppress the demonstrators. Almost 1000 demonstrators have been detained. The police force formed nine working groups responsible for different aspects of the conference, drawing manpower from all over the force. The working groups included: logistics; traffic management; manpower and procurement; public relations; command and control; IT and communications; public order; security; and tactics and training. To stop protesters, fences around the Hong Kong Convention and Exhibition Centre were erected. French windows of shops, including McDonald's in Sun Hung Kai Centre, which is close to the Wan Chai Sports Ground protest zone, were surrounded by wire nettings. The Wan Chai Cargo Handling Basin in Wan Chai, which was also assigned as a protest zone, had fences surrounding the area. The ground of the Cargo Handling Basin was also levelled. Drain covers outside Wanchai Tower were secured, and bricks on the ground in Wan Chai also glued together to prevent protesters from digging them up. Nets were placed around footbridges in Wan Chai and Causeway Bay to prevent objects from being thrown onto the roads. The seven commercial buildings around the Hong Kong Convention and Exhibition Centre, for the first time, formed a security network, under which their closed-circuit television systems were linked together during the period of the conference.