Ching said the pair were detained on suspicion of killing the 33-year-old victim, who allegedly worked as the operator of a gambling den on Pilkem Street in Yau Ma Tei.

He said the three other suspects, aged 34 to 56, were apprehended for aiding and abetting the alleged attacker.

“We reasonably believe these three arrestees were aware of the [alleged murderer] who had committed the crime and assisted him in evading arrest,” Ching said, adding further arrests were possible as the investigation was ongoing.

The alleged murderer and the victim had a history of disputes as the former thought the latter was dating his girlfriend, according to police.

At around 2.20am on Sunday, the alleged attacker and his girlfriend went to the gambling den to look for the 33-year-old victim. The trio left the premises afterwards.

“Initial investigations revealed that [the attacker] suddenly used a hammer to strike the back of the victim’s head over 10 times [outside the building],” the superintendent said.

According to Ching, the murder suspect and his girlfriend left the scene soon after and dumped the weapon in a rubbish bin.

The victim was still conscious and returned to the gambling den. But he complained of feeling unwell at around 6am and passed out after friends carried him downstairs.

The victim was taken to Queen Elizabeth Hospital in Yau Ma Tei, where he was pronounced dead at 7.20am.

“An initial examination revealed the victim had two lacerations on the back of his head, measuring around 2cm and 4cm [1.5 inches] respectively,” Ching said, adding that an autopsy would be carried out to determine the exact cause of death.

A preliminary investigation suggested a personal dispute between the attacker and the victim sparked the killing and there was no evidence the attack was linked to triad activities or illegal gambling, he added.

The Post learned that the victim was a suspected member of the 14K triad gang while the alleged murderer was said to be a member of the Wo Shing Wo.

After an extensive investigation, officers arrested the 32-year-old woman in Yau Ma Tei at around 12.50pm on Sunday.

The alleged attacker and the three other suspects were apprehended in Ho Man Tin about nine hours later.

Officers raided the gambling den and seized paraphernalia related to illegal drugs such as crystal meth.

A source familiar with the case said police were investigating whether the alleged murderer had taken illegal drugs before the attack.

As of Monday morning, all five suspects were being held for questioning.

Detectives from the Yau Tsim district crime squad are following up on the case.

The city recorded eight reports of homicide in the first five months of this year, three cases fewer than the 11 recorded in the same period in 2023.

A 66-year-old businessman and his 57-year-old wife died last Wednesday after he allegedly set fire to their flat in the Mid-Levels over suspected marital issues in what police said was a murder-suicide.