Hong Kong police said a 19-year-old man pulled a semi-automatic pistol from his waistband as officers approached him in Tai Po district on Friday evening. The officers tried to arrest him in an operation linked to the months of pro-democracy protests engulfing the city.
A shot was fired in the tussle, but the shot did not hit anyone and the man was subdued.
Post the search of a nearby flat, police uncovered an AR-15 semi-automatic rifle and more than 250 rounds of ammunition.
Senior Superintendent of the Police Organised Crime and Triad Bureau Steve Li said there were signs that the man was linked to a group arrested earlier this month who was also allegedly found in possession of a pistol and were plotting to attack officers.
"The firearms we discovered matched the intelligence we had collected which indicated that some people hoped to use firearms in some public assemblies to wound some others, including police officers on duty," Senior Superintendent Lee Kwai-wah said.
According to the police, the arrested man was facing ongoing firearms charges from an arrest last year before the protests.
Hong Kong police in the meantime have frozen $10 million from a major fund that was meant to help pro-democracy protesters. The police instead arrested four members of Spark Alliance, a non-profit online platform on money laundering charges.
On Friday evening, hundreds of Hong Kong anti-government activists gathered outside a detention centre and demanded the release of arrested activists.
Protesters in Hong Kong have been angry over Beijing's meddling in the 'one country, two systems' formula China agreed on when Hong Kong returned to Chinese rule in 1997.
They were initially sparked by a now-abandoned attempt to allow extraditions to the authoritarian mainland but have since morphed into a popular revolt against Beijing's rule.
While the protests have largely been peaceful, a newly radicalised youth armed with petrol bombs, bricks and sometimes bows and arrows has added a dangerous layer to the movement, leading to increasingly violent battles with riot police.
In recent weeks, police have made arrests indicating some protesters may be plotting more drastic action.
Alongside the arrest earlier this month of a group of people in possession of a pistol, police said they also discovered two homemade nail bombs that had been stored in the grounds of a school.
Both Lam and the Hong Kong police force's reputation have taken a hammering during the protests but Beijing has publicly backed both.
