Four people were wounded on Tuesday in a shooting in a Hong Kong park next to a busy shopping center, a rare gun attack in a city ranked as one of the safest in the world.

A woman was arrested after she used a gun to shoot at two men and two women, a police spokeswoman told Reuters.

Television stations showed footage of an elderly man lying on the ground beside a pool of blood, and another person with a head wound. The four victims were taken in stretchers to ambulances.

Scores of police officers with guns and bullet-proof vests descended on the area.

The motive was not clear but media reported that the victims were related and involved in a family dispute.

A hooded person in a pink polo shirt and jeans was later taken away by police.

The shooting took place in the mid-afternoon in Quarry Bay, to the east of the Central district on Hong Kong island, in a park next to Cityplaza shopping center.

Police cars lined the roads and part of the leafy park was cordoned off.

The leader of the Chinese city, Carrie Lam, said the former British colony was safe with a crime rate of 758 cases per 100,000 people in 2017.

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