Lee said authorities would take law enforcement action against those responsible for installing unauthorised structures. As well as the legal repercussions, there would also be an expectation that they would cover the costs of repairs carried out by the government, he said.

“That includes prosecution if they are found to have broken the law. They will be expected to take responsibility for the cost of government engineering work resulting from their unauthorised structures,” he said.

Illegal structures found at second Hong Kong home after landslide strikes estate

The controversy centres on three houses at Redhill Peninsula – No 70, No 72 and No 74 – damaged by a landslide following record-breaking downpours last week that triggered a black rainstorm warning for more than 16 hours.

The Lands Department confirmed on Tuesday night that all three houses had occupied government land without permission, after reviewing aerial photos and relevant plot plans. But it did not specify which parts of the houses were involved.

It added it had commenced emergency slope maintenance works and would take serious enforcement action.

“Subject to weather conditions, the contractor expects to complete the more critical parts of the works within a few days and complete all works by late September,” it said.

Authorities confirmed on Sunday that house No 72 was found to have illegal structures and had unlawfully occupied government land. Occupants were evacuated amid risks of unstable soil.

The Buildings Department on Monday said unlawful additions were also found at house No 70, with a five-by-13-metre (16.4-by-42.6-foot) structure discovered on its lowest podium and a five-by-six-metre basement behind it.

In a dramatic twist, the department said on Tuesday night that it would apply on Wednesday for a court warrant to enter No 74, after the owner refused to allow its officers to enter some areas of the house where unauthorised structures were suspected to be present.

Hong Kong luxury house, evacuated after landslide, has illegal structures: minister

The department had earlier said it would examine house No 74 on Tuesday after finally getting a nod from the occupants who previously refused inspectors access to the home.

On Tuesday morning, several trucks loaded with debris, bamboo and rolls of metal net were seen at the estate. Department officers also entered the estate at 10am.

Workers erected scaffolding near the slope in front of No 70.

04:04

More than 140 injured as Hong Kong faces 'once-in-500 years' downpour

More than 140 injured as Hong Kong faces 'once-in-500 years' downpour

The Hong Kong Institution of Engineers said it regarded the record rainfall and the unauthorised structures on the slope as reasons for the landslide.

“But so far we can’t tell which one is the major reason for the incident as experts still need to check the site and carry out analysis,” said Kevin Tang, chairman of the body’s structural division.

“Maybe the checks will discover another reason.”

Tang also estimated that it would cost at least HK$1 million (US$173,000) per home to stabilise the slope with the unauthorised structures. But he could not put a final price on the repairs, only that they would “surely” cost a fortune.

“If it is confirmed that construction was not approved by the Buildings Department, it is considered illegal unauthorised construction, and the responsibility lies entirely with the property owner,” Tang said.

Chris Lee Tsz-leung, former chairman of the institution’s geotechnical division, said there was potential for another landslide at Redhill Peninsula given that the slope had not yet been fixed and it was still the rainy season.

All three houses are located on Cedar Drive at Redhill Peninsula Site D.

No 70 is a 2,743 sq ft four-bedroom house and was last sold in April 2006 for HK$38.5 million. The house is understood to be owned by Superhold Limited.

One of Superhold’s directors is Johnny Chan Kok-chung, who shares the same name as Cyberport’s chief investment officer.

Hong Kong rainstorm alerts to be enhanced, drainage works prioritised: John Lee

The four-bedroom 3,013 sq ft house No 72 most recently exchanged hands in March 2011 for HK$73 million.

The property is understood to be owned by Petrina Anne Steains and Anthony John Steains. The latter shares the same name as the former head of Blackstone Advisory Partners in Asia, the world’s largest private equity investment firm.

No 74, the same size as No 72 and also four-bedroomed, was last sold in November 2006 for HK$39 million.

The Post has learned the house is owned by Future Ocean Limited, whose sole director Deborah Yuen Wai-ming shares the same name as a member of the Community Chest Fund’s public relations committee.

The Post is unable to independently verify the names of the individual owners. Attempts to contact them were unsuccessful.