The move is being taken after complaints from people who were denied entry to the public areas.

Real estate developers and construction firms were given incentives to add more floor space to commercial or residential buildings if they agreed to donate a part of adjacent land parcels as “open space” for the public.

A few property owners have donated the “open space” as public parks or green areas.

But most have built up high walls and gates to keep such “open space” to themselves as private gardens, parking lots or for other uses without honoring the earlier agreements made when applying for construction licenses.

City government officials said two of the cases have been rectified following complaints.

They will conduct a sweeping check on more than 2,200 cases in three phases. Those refusing to make improvements will face fines.

They encouraged residents to use the “1999” telephone hotline to report the construction projects violating the regulations.