Bulletproof glass and two-tonne barriers are among the more obvious security measures Hong Kong is putting in place ahead of Chinese President Xi Jinping’s visit this week, but some of the preparations involve a far more nondescript item – glue. About 10 workers were seen using glue to reinforce the pavement in Tim Mei Avenue outside the Central Government Offices and Legislative Council Complex at about 10pm on Tuesday. A force insider said the move was to prevent people from digging up bricks. Such work would be carried out at other sites if necessary, the source added, confirming that this was part of the enhanced security for Xi’s trip. The same tactic was used in Wan Chai before state leader Zhang Dejiang’s visit in May last year. Police employed this security measure for the first time when the city hosted the World Trade Organisation summit in 2005 to prevent protesters, mostly South Korean farmers, from digging up bricks to attack officers with. During the Mong Kok riot in February last year, rioters dug up about 2,000 bricks from pavements to attack police. The clashes left about 100 officers injured. Air-land-sea security measures are being put in place in the city before Xi and his wife, Peng Liyuan , land at Hong Kong International Airport on Thursday. The president will be in town to mark the 20th anniversary of Hong Kong’s handover to China. On Wednesday afternoon, officers from the force’s elite search team will carry out a search for threats at the Convention and Exhibition Centre in Wan Chai, where on Saturday morning, Xi will oversee the swearing-in of Carrie Lam Cheng Yuet-ngor as chief executive before leaving the city in the afternoon. President Xi Jinping no stranger to Hong Kong following trade trips In the evening, security equipment, including an X-ray machine, will be set up at the Renaissance Hong Kong Harbour View Hotel , where the president and first lady will stay. Similar measures will be in place at the adjacent Grand Hyatt hotel, where Xi’s delegation will put up. To prevent vehicle attacks, about 300 barricades, weighing two tonnes each, will ring the two hotels and the Convention and Exhibition Centre. The set-up is expected to be completed by Wednesday. According to police, the security zone in Wan Chai North is larger than during previous operations. Road closure in the Wan Chai area will begin at about 8pm on Wednesday. A restricted flying zone above Wan Chai and Victoria Harbour will be in place between 9am on Thursday and 6pm on Saturday, with Government Flying Service helicopters being deployed. More than 10 marine police boats are expected to conduct 24-hour patrols around Victoria Harbour during Xi’s trip. The security measures are expected to affect traffic in Admiralty and Wan Chai North. Police will keep inconvenience to the public to a minimum while striving to ensure a safe visit for the president, a spokesman said. Over the next three days, about 11,000 of the city’s 29,000 police officers will be involved in the security arrangements.