What started as an early morning pub brawl at Orchard Towers left one man dead, and eight people, including two women, have been arrested in connection with the case which the police have classified as murder.
Employees arriving for work yesterday morning were shocked to see the 31-year-old victim on the ground at the building's entrance in a pool of blood.
Earlier, those in the building had heard people shouting and fighting.
Closed-circuit television footage from a shop on the first floor showed a group of about 10 men and women walking towards the victim and striking him after he stepped off an escalator and approached one of them.
The victim exchanged several blows with members of the group, and was later cornered by them.
The group subsequently left, and the man fell in front of the building's glass doors. He seemed to be bleeding from his neck, according to footage seen by The Straits Times.
The man was taken to Tan Tock Seng Hospital, where he was pronounced dead at 7.25am.
When The Straits Times arrived at the scene at about 11am, the police, who had been alerted at 6.25am, were seen gathering evidence, including a mound of blood-soaked tissue, near the building's cordoned-off entrance.
At 1pm, most of the building's second floor and main entrance still remained out of bounds for investigations.
Police officers were seen speaking to people at the Naughty Girl Club on the same floor.
In a statement yesterday evening, the police said eight suspects between the ages of 22 and 27 were identified and arrested within 12 hours.
Four of the men and one woman were expected to be charged with murder with common intention tomorrow, according to the statement, which said investigations were still ongoing regarding the rest.
A murder conviction could result in the death penalty.
Mr Muhammad Bilel, 40, who works at a convenience store on the first floor, said his colleague who was on the early morning shift had heard a commotion outside the store. "He heard a lot of people shouting and fighting, but he couldn't go out because he had to look after the shop," said Mr Bilel.
Another store owner, who requested not to be named, said her workers had called her in panic at around 7am.
"They were all so scared. When they arrived, they saw someone lying on the floor outside the building's entrance," she said.
She added that the fight had reportedly started inside Naughty Girl Club, but the group had continued fighting on the first floor.
An employee of May Tailor and Alteration said footage of the incident has been circulating among the building's tenants.
"Someone took a video of the paramedics trying to save the man, and I could see there was blood all around his body," she said.
Deputy Commissioner of Police (Investigations and Intelligence) Florence Chua commended the officers for their work.
"The police are committed to keeping Singapore safe and we will spare no effort to track down offenders to ensure that they are brought swiftly to justice and face the full brunt of the law," said DCP Chua, who is also the Criminal Investigation Department chief.