Hong Kong’s labour minister has vowed to look into possible violations of legal procedures to approve and install a 65-tonne tower crane that collapsed and killed three workers at a public housing construction site last week.

Secretary for Labour and Welfare Chris Sun Yuk-han suggested on Saturday that the Labour Department should join work safety meetings held by the Housing Society, which builds public flats and is responsible for the site in question.

“The design, installation and the approval of the tower involves legal procedures, with someone signing the relevant documents which could be the basis of our investigation,” he told a radio programme.

Secretary for Labour and Welfare Chris Sun.

In the tragedy last week, the tower crane, suspected to have had “obvious faults” at its base, collapsed and killed three workers and injured six others at the site on Anderson Road in Sau Mau Ping.

Sun said both police and the Labour Department were conducting investigations. An independent expert was helping the department in its work, and the major direction of the inquiry would be the faults in the tower base, he added, stressing the investigation would take time as the case was complicated and involved professional judgment.

Police were also looking into possible criminal liability to determine if negligence was involved, he said.

Works at the construction site, including that of nine others under the same contractor, have been suspended and cannot resume till authorities are convinced its cranes are safe, according to Sun.

He pledged to disclose the investigation findings to the public.

In another televised interview, Sun said the department should also join the work safety meetings on private projects held by the Housing Society. Currently, it only attends meetings on large-scale public projects.

On a separate accident involving a concert by boy band Mirror in July, Sun said the department had already gathered the contract details of dancers who were injured by a giant falling screen.

Police gather evidence at the Hong Kong Coliseum as part of an investigation into a horrific stage accident.

Two performers Mo Li Kai-yin and Chang Tsz-fung suffered severe injuries when the four-by-four-metre device crashed onto the stage at the Hong Kong Coliseum. Li is in danger of being paralysed from the neck down.

Sun said the department, which was seeking legal options, would find out if the dancers were self-employed, and details would be disclosed later.