The Independent Commission Against Corruption (ICAC) has arrested 22 individuals in connection with suspected corruption and illicit activities tied to large-scale renovation projects at seven housing estates and buildings across Hong Kong.

The arrests follow a two-day enforcement operation, codenamed "Lion Rock", conducted between February 9 and 10.

The operation targeted grand renovation works at three housing estates, three residential buildings and an industrial building in districts including Tsuen Wan, Sham Shui Po, Tai Kok Tsui, San Po Kong, Kwun Tong, Sheung Wan and Shau Kei Wan.

The ICAC said individual project contracts ranged from HK$2 million to over HK$100 million, with the total value of all contracts exceeding HK$200 million.

Two of the projects, collectively worth more than HK$100 million, were still in the preparatory stage and were halted after the ICAC intervened to prevent the contracts from being awarded.

Of those arrested are 17 men and five women, aged 36 to 78.

They include directors and staff from four project consultancy firms and three contractors, as well as several chairpersons of incorporated owners (IO) committees from the affected buildings and estates.

During the operation, ICAC officers executed search warrants at multiple locations, including the offices of the consultancy firms and contractors.

Evidence seized, they said, included tender documents, works records, banking statements and accounting files.

The investigation was sparked by a corruption complaint alleging that contractors had offered bribes to consultancy firms and IO members in exchange for assistance in securing renovation contracts.

Authorities uncovered that consultancy firms and contractors had allegedly falsified accounting records to conceal irregular income and expenses.

The ICAC also revealed that one IO chairperson is suspected of leaking confidential tender interview questions at the request of a consultancy firm, in an effort to help the firm win a contract.

Officers have indicated that the investigation is ongoing and further enforcement actions have not been ruled out.