Asbestos experts will be fencing off Rennie's Mill in two weeks to remove hazardous building material ahead of demolition of the Tseung Kwan O squatter area. Bulldozers are expected to knock down the 1,940 cottages by the end of the year, concluding the final chapter of the nationalist stronghold. Dredgers are moored off Rennie's Mill to prepare for reclamation that will change the shape of the former coastal settlement. The slum area is to be transformed into a new hub of eastern Kowloon, with an MTR extension, schools, parks and estates to house about 400,000 people by 2011. The Housing Department plans to build 12,000 home ownership and rental units on the site. An asbestos survey is expected in the middle of next month after the 54 hectares of land is declared a no-go zone, according to the department. The toxic material is commonly found in canopies or roofs of blocks built in the 1950s and 1960s. The huts will have to be sealed and workers have to wear protective clothing before asbestos is removed. The department's assistant director, Lau Kai-hung, said that after removing the five remaining diehard families yesterday, demolition could start as early as December. Mr Lau yesterday offered a reprieve to 229 households, allowing them to stay for another two weeks to pack their bags. Yesterday's clearance saw militant squatter Lydia Yang Lee Yue-lam and her husband, Yang Pui-chi, wield an axe and carving knife to confront Mr Lau when he tried to persuade the couple during a 75-minute stand-off. Mrs Yang also scared off workers when she threatened to ignite a liquefied petroleum gas cylinder and roared at officers: 'If you dare to evict, we shall die together.' She eventually surrendered but vowed to hold a marathon sit-in outside Mr Lau's office. Her mother-in-law, Yang Yiu-lin, 84, complained of a headache and was taken to see a doctor after the confrontation.