HONG KONG - The Sham Shui Po police station in Hong Kong was besieged by more than 300 people on Tuesday (Aug 6) night after a student leader was arrested in the district, prompting police to fire tear gas to try to disperse the crowd.

The crowd had vandalised the building and flashed lasers at the building after the police arrested Keith Fong Chung Yin for carrying offensive weapons, namely 10 laser pointers, reported the South China Morning Post (SCMP).

Several rounds of tear gas were fired at around 11.20pm to disperse the crowd. Fong was not inside the police station at the time as he had been moved to hospital.

He is student union president at Baptist University and was arrested at the junction of Apliu Street and Kweilin Street, a few blocks from the police station.

He was sent to the nearby Caritas Medical Centre after complaining of feeling unwell.

Chief Inspector Chow Hok Yin from the organised crime and triad bureau said Fong was approached by officers because he was acting suspiciously. He was caught by the officers after a chase and 10 torch-like laser pointers - each 18cm-long - were found in his plastic bag.

The pointers, which a police source said is strong enough to burn paper, are regularly aimed at officers during protests and clashes.

"If anyone uses such an object to attack a person, it could also be deemed an offensive weapon," said Chief Inspector Chow.

"In recent operations, you can also see people flashing such laser pointers at police officers. Some of us have felt unwell, while some were even injured."

The arrest was first confirmed by the student union on social media in the evening. The union accused the police of abusing their power, SCMP reported.

University president Professor Ronald Chin Tai Hong and a lawyer were at the hospital with Fong.