Details of the massacre were made public yesterday after family members flew to the Philippines to inspect the crime scene, which had not been touched at their request.

Hong Kong's art and business community last night paid tribute to the three men, expressing shock and horror over the murders.

The victims were stabbed repeatedly in their beds as they slept and were found early on Sunday at the German's three-storey villa at a residential development called La Dolce Vita, or The Sweet Life, where Schoeni had just bought a block.

The villa, the first of six to be built on the hilltop site, is considered one of the most luxurious properties on the island famed for its white-sand beaches.

'We are looking at robbery [as a motive for the murders] and we have some people here who we are questioning,' Superintendent Remus Canieso, chief investigator and head of the island's security force, said yesterday.

He said all four victims died of stab wounds from two large kitchen knives, which were recovered from one of the lavatories. One knife was described as a 'cutting knife', while the other was 'like a bread knife, serrated and pointed at the end', the police chief said.

All three foreigners were found in separate bedrooms on the second floor of the three-storey villa. Sarmiento was found in her bedroom on the first floor.

There were no signs they had been killed elsewhere then dragged into separate rooms, Superintendent Canieso said.

He said there were no signs of forced entry.

'The [main] door was opened from the inside. Yes, somebody let them in,' he said. 'The door was not forced open; no windows were broken.'

Police are interviewing the 25 construction workers who were employed on various parts of the one-hectare estate, as well as the boyfriend of the housemaid.

The owner's wife, Josephine, Schoeni's ex-wife Wai-yin and Cowperthwaite's son Adam flew in from Hong Kong yesterday to inspect the bloody scene. Adam Cowperthwaite, a Hong Kong stockbroker, did not wish to comment when contacted by the Post last night.

Swiss Consul-General Francois Barras said the murder of millionaire art dealer Schoeni, who had lived in Hong Kong for nearly 30 years, was a 'great loss for the entire Hong Kong community'.

'Manfred was one of the pre-eminent members of our community and we regret very much his loss,' he said.

'He contributed greatly to the artistic life of this city.'

Greg Hutchinson, owner of SandCastles, a Boracay resort favoured by Hong Kong tourists, said the island's foreign residents were stunned by the killings.

'It came as a shock to me because Boracay had been increasingly friendly, good-natured and crime-free,' Mr Hutchinson said.

'Most of us are numb. We hate the idea of what we think is paradise being smudged by killings.'