Hong Kong is bracing for a rowdy and possibly hugely dangerous Halloween on Thursday, when thousands of pro-democracy protesters, many wearing banned face masks, plan to combine with fancy-dress clubbers in the party district of Lan Kwai Fong. The protesters say they will march, without police permission, from a park in the Causeway Bay shopping district through the heaving bar streets of Wan Chai to the steep, narrow foothills of the Peak above Central. Every weekend, the bars in Lan Kwai Fong spill on to the streets office goers, clubbers and expatriate families, even without the activists who have thrown petrol bombs at police, set fires and trashed buildings during five months of unrest. A stampede at midnight on New Year's Eve in 1992, when thousands had gathered, killed at least 20 and wounded scores. This month Hong Kong leader Carrie Lam banned protesters from wearing face masks under a resuscitated British colonial-era emergency law, but few have taken any notice. And Halloween masks have not been banned, which will make it difficult for police to identify protesters. "Based on past experience, such unauthorized assembly will impose serious threat to public order and public safety," police said in a statement. "Members of the public should avoid traveling to the concerned area when public disorder occurs." 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. Some are increasingly focusing their fury on mainland Chinese in the city. China denies meddling and has accused foreign governments, including the United States and Britain, of stirring up trouble. Lam said she expected negative economic growth in the Asian financial hub this year, in part as a result of the unrest. "The increasingly violent reality since June is hurting Hong Kong's economy," Lam said in a speech on Wednesday. "...what started off as peaceful protests, a hallmark of Hong Kong's rights and freedoms, have turned into violent acts by rioters." With visitors deterred by months of violence, many small firms across the city have already closed or are struggling to turn a profit. Lam's gloomy forecast came two days after Financial Secretary Paul Chan said Hong Kong had slipped into a technical recession, meaning two successive quarters of contraction. That is expected to be confirmed by Thursday's third-quarter GDP data. The protests, which started over a now-withdrawn extradition bill, have plunged the city into its biggest crisis in decades and also pose the biggest populist challenge to Chinese President Xi Jinping since he came to power in 2012. -Reuters