Ronald Leung Kam-shing is the convener of the North District Parallel Imports Concern Group, which has helped to organise protests over the past few years urging the government to curb parallel trading in the district, including the latest march in Sheung Shui last month .

A Hong Kong anti-parallel trading activist was attacked near his residence on Sunday night. His assailants reportedly warned him “not to stir up trouble again.”

The practice of parallel trading relates to salespeople exploiting a multiple entry visa policy to import tax-free items from Hong Kong across the border. Leung’s group has said the activity often results in a shortage of goods and elevated retail prices, forcing shops to either close down or cater to mainland tourists.

At around 11:20pm on Sunday, Leung was walking around Shing Mun River in Sha Tin near his flat when he was ambushed by four to five men, according to activist Max Chung — a friend of Leung who visited him afterwards at the Prince of Wales Hospital, where he was receiving treatment.

Chung said the group of unknown men attacked Leung with weapons that appeared to be bamboo sticks, leaving him with bruises. They then threw unidentified white powder on Leung’s face.

The assailants spoke in Cantonese with an accent that appeared to be from mainland China, Chung said.

He added that the activist was directly threatened by name: “Leung Kam-shing, stop fucking stirring up trouble. This is a warning. It won’t be like this the next time,” Leung recalled them saying.

Chung said that police on the scene refused to send Leung to hospital for treatment after discovering that he did not have an identity card with him.

After the attack, reporters at Apple Daily and Ming Pao — two major newspapers — received telephone calls from unidentified male callers telling them to go to the Prince of Wales Hospital and cover the incident.