HONG KONG — Hong Kong riot police faced off with protesters occupying a suburban train station Wednesday evening following a commemoration of a violent attack there by masked assailants on supporters of the antigovernment movement.
Near the end of the event, the police began what they called a ‘‘dispersal operation, using minimum force’’ after some protesters blocked roads and flashed laser pointers at officers.
The group of remaining protesters had sprayed a firehose, spread oil on the floor, and piled up trash bins, a wheelchair, and umbrellas to slow the approach of the police.
They also discharged fire extinguishers, creating a foggy cloud obscuring visibility. The station’s entrance shutters were lowered, barricading the protesters inside.
The black-clad protesters flooded earlier into Yuen Long station to commemorate the July 21 rampage by a group of men suspected of organized crime links, in what was a shocking escalation of the city’s summer of protest.
The protesters observed a moment of silence, then covered their right eyes, a reference to a woman who reportedly suffered a severe eye injury from a police projectile.
Many sat on the station floor, while others walked slowly around the concourse in a protest march.
They also drew attention to what they say is the lack of progress by police in investigating the attack, which left both protesters and passersby injured. Protesters have accused the police of colluding with the attackers by pointing to their delayed response, but authorities have denied it.
Police say they have arrested 28 people in connection with the attack but haven’t charged anyone yet. They say some of those arrested have triad links, referring to organized crime syndicates.
The antigovernment protests began more than two months ago and have spiraled into a political crisis, with supporters demanding full democracy and an investigation into alleged police brutality.
Also Wednesday, China said a staffer at the British consulate in Hong Kong has been given 15 days of administrative detention in the neighboring mainland city of Shenzhen for violating regulations on public order.
The case is stoking fears that Beijing is extending its judicial reach to semiautonomous Hong Kong.
‘‘The relevant employee is a Hong Kong resident, not a British citizen,’’ so the case is ‘‘purely the internal affairs of China,’’ foreign ministry spokesman Geng Shuang said at a daily briefing.
A small group of supporters gathered outside the British consulate to demand the UK government step up efforts to secure the release of the man, Simon Cheng Man-kit, chanting ‘‘Save Simon now!’’
Foreign Minister Wang Yi said China brooked no foreign interference in Hong Kong but understood foreign countries’ concerns about the safety of their citizens and investments and was determined to maintain the territory’s stability and prosperity under the ‘‘one country, two systems’’ framework, which gives Hong Kong wide autonomy.