An emergency operation will be launched in the next 10 days to inspect 30 buildings in Ladies Street, Mongkok, following the death of a hawker. Chief building surveyor Edmond Li Siu-kwan said immediate action would be taken against owners if any dangerous structures were found in the 30-plus blocks between Argyle Street and Nelson Street. The Buildings Department action is aimed at allaying fears among the public and the area's many hawkers who are anxious they could be the next victims as many of the blocks are between 20 and 30 years old. Lingerie hawker and mother-of-two Liu Ngan-fong, 41, was killed instantly when hit by a 6.5kg lump of concrete which plummeted 12 floors from the 35-year-old Kwok Wing Building in Tung Choi Street, better known as Ladies Street. 'We believed the roof of the unit where the slab fell from is an illegal structure,' Mr Li said, adding that more than 10 external structures of the building, such as the balconies, were also illegal. Chairman of the building's newly set up owners' incorporation, Shek Hon-kei, disclosed it was a rented unit and the flat owner had renovated the external wall last summer. 'But the unit's owner has not showed up since the accident. We don't know where he is now,' Mr Shek said. The Buildings Department dismantled a ceiling at the entrance to a shopping centre at 406 King's Road, North Point, after part of it collapsed on Wednesday night. No one was injured. Inspectors discovered it, too, was an illegal structure.