Protesters in Hong Kong suspended talks with authorities on Friday night alleging "organised" attacks by mobs, in less than 24 hours after agreeing to meet a senior official for a dialogue on constitutional reform.
The Hong Kong Federation of Students said it had "no other option but to call off the talks" aimed at bringing an end to the days of massive demonstrations that has paralysed the city for a week.
The South China Morning Post reported that the students announced they will officially call off its meeting with Chief Secretary Carrie Lam.
"The government and police today turned a blind eye to violent acts by the triads targeting peaceful Occupy protesters", said the protesters who were out on the streets to press for their demand that Beijing restart the constitutional reform process and roll back rules that China would vet candidates for the first direction election of city's chief executive in 2017.
The incumbent chief Leung Chun Ying urged the pro-democracy protesters to disperse for their own safety, even as scenes of mobs tearing up tents and destroying the protesters' supplies like bottled water and food were witnessed earlier in the day in Mongkok district.
Mr Leung called for calm in a statement televised on Friday night and said he did not want any harm to come to protesters.
Police also denied allegations that they did little to protect protesters from the violence. Senior Superintenden Kong Man-keung told reporters: "We tried our best… to protect lives down there."
But activists alleged the attacks were "organised".
Police said there had been two arrests and defended their response to the chaotic scenes, with senior superintendent Kong telling reporters the force had "deployed a lot of manpower to control the situation". Protesters reacted angrily to the lack of arrests, saying pro-Beijing thugs had been freely allowed to attack their camps. The crowds in Mong Kok chanted "Bring out the handcuffs!" late into the night. Police officers were seen escorting a man from the scene with his faced covered in blood.
They also urged their supporters to leave areas where they were under threat and consolidate their position in the Admiralty district, where crowds are maintaining their week-long blockade of Mr Leung's office and the central government complex.
The protesters have massed on the streets in fury at China's announcement in August that while Hong Kongers can vote for their next leader in 2017, only candidates vetted by Beijing will be able to stand - a decision dismissed as "fake democracy" by campaigners. Demonstrators had set a midnight Thursday ultimatum for Leung to resign and for Beijing to abandon the proposals to vet candidates.
Mr Leung - seen by the protesters as a Beijing stooge - refused to quit, but in a dramatic televised appearance shortly before the midnight deadline he appointed his deputy to sit down with a prominent students' group that has been at the vanguard of the protests.
Mistrust was rife that Mr Leung was merely trying to buy time in the hope that Hong Kong's residents will tire of the disruption caused by the mass sit-ins. Friday's clashes broke out as the city returned to work after a two-day public holiday.
(Input from AFP)