Some shone lasers at police shouting "Hong Kong people resist" as others built barricades in the road with rubbish bins.
Hong Kong police fired tear gas to break up anti-government protests in the densely populated Kowloon district of Mong Kok on Thursday, as masked demonstrators gathered to join Halloween fancy-dress clubbers on the other side of the harbour.
Hundreds of protesters, many dressed all in black and wearing now-banned face masks, knelt in the key artery of Nathan Road and took cover behind umbrellas, angry at a violent police crackdown on unrest there two months ago.
Some shone lasers at police shouting "Hong Kong people resist" as others built barricades in the road with rubbish bins, plastic seats and other debris, a familiar tactic in five months of often violent unrest.
They blocked off intersections on Nathan Road targeted by activists last weekend, smashed lampposts and pried away bricks and other debris from the paths and shop fronts, hidden from view by others holding umbrellas.
"Having given repeated warnings to the protesters in vain, the police officers have deployed tear gas and will use minimum necessary force to disperse protesters," police said in a statement.
The demonstrators on the main island were gathering at Victoria Park in the Causeway Bay shopping district to march to the hilly, narrow streets of the Lan Kwai Fong bar district above Central, the scene of a deadly New Year's stampede nearly 27 years ago.
Some were wearing Guy Fawkes masks and others were made up as clowns. One reveller already in Lan Kwai Fong was dressed in red, apparently modelled on the star character in the dark Hollywood hit movie "Joker".
"Stop blocking the road. Fuck you," they shouted at the police. "We want to drink. Can't you let people have some fun for once?"
One reveller with the clown dressed in red, who gave his name as Gordon, 43, said: “I hope no police, no war tonight. Everyone is happy” as he walked away shouting “liberate Hong Kong”.
Police have banned the march and said they would close roads, including the short Lan Kwai Fong street itself, until Friday morning to "facilitate the public celebrating." It was not immediately clear how they would distinguish between party-goers and protesters.
It is the first time protesters have targeted the party district in five months of increasingly violent, anti-government unrest. Typically, weekends and celebrations like Halloween see hordes of revellers spilling out of the bars and clubs on to the streets.
A stampede during New Year celebrations at the end of 1992, when thousands had gathered on streets slippery with beer and champagne, killed at least 20 people and wounded scores.
Police, who have been warning for days of the threat to public order and safety, were deploying 3,000 riot officers and three water cannon outside government offices near the route, according to media.
Hong Kong, as widely expected, slid into recession for the first time since the global financial crisis in the third quarter, data confirmed on Thursday, weighed down by increasingly violent anti-government protests and the protracted US-China trade war.
Hong Kong's central bank also cut rates on Thursday in step with the US Federal Reserve.
Britain urges restraint
Pressed on government plans to relieve the hit to businesses in Hong Kong from the protests, Hong Kong leader Carrie Lam told a conference the circumstances warranted "exceptional" measures.
"If we still act in the same conventional mode as if the business is usual and life is normal, then we are not being very responsible," she said.
Her administration has pledged around $2.68 billion of financial aid for business since August, from rent to fuel subsidies.
The protesters are angry at what they see as Beijing's increasing interference in Hong Kong, which returned from British to Chinese rule in 1997 under a "one country, two systems" formula intended to guarantee freedoms not seen on the mainland.
China denies meddling and has accused foreign governments, including the United States and Britain, of stirring up trouble.
British Foreign Secretary Dominic Raab said on Thursday Hong Kong should seek ways to de-escalate tension and find a political resolution, calling on both protesters and authorities to show restraint.
China said after a meeting of its top leadership that it would safeguard Hong Kong's prosperity and protect national security.
Some protesters in Hong Kong have thrown petrol bombs at police, lit fires and trashed government buildings and businesses, especially those seen as pro-Beijing, during recent demonstrations.
Police have responded with tear gas, pepper spray, rubber bullets, water cannon and several live rounds.
Hong Kong's subway operator MTR Corp, which has also been targeted by protesters, said it would shut some stations earlier than usual. Central station, a few minutes walk downhill from Lan Kwai Fong, will shut by 9 pm.