HONG KONG • A family dispute in Hong Kong turned fatal yesterday when a woman allegedly fired a gun at her relatives, killing her 80-year-old aunt, who took a bullet to the head.

The shooting at Quarry Bay Park also injured the dead victim's three siblings, two men and a woman aged 60 to 72.

One of them, a 63-year-old man, was in critical condition after he was shot in the lung, head and arm.

Both his surviving siblings sustained gunshot wounds in the arm, Apple Daily reported.

Police were alerted to the attack at around 3pm and scores of officers with guns and bullet-proof vests descended on the area.

They detained a female suspect, 44, at the nearby Cityplaza mall.

"We believe the woman to be the assailant and we recovered a firearm from her possession," chief inspector Hui Hong Kit told the press.

He said preliminary investigations suggest the attack at the harbourfront park, which is to the east of the Central district on Hong Kong Island, was motivated by a "family conflict" and was not linked to organised crime.

The wounded are brothers and sisters, he added, while the alleged shooter - who used a semi-automatic pistol - is their niece.

Heavily armed police officers were seen apprehending the suspect who was clad in jeans and a polo top, and pinning her to the ground as the alleged weapon lay near her, Apple Daily reported.

Hong Kong Chief Executive Carrie Lam said that the former British colony, which has a crime rate of 758 cases per 100,000 people last year, was safe.

"Cases involving firearms and assault are very, very rare, so we are paying great attention to this case involving a firearm hurting other citizens," she told reporters.

Shootings and gun-related incidents are unusual in the semi-autonomous Chinese territory.

Under Hong Kong law, no one is allowed to possess any arms or ammunition unless they hold a permit for possession or a dealer's licence.