New clashes broke out between protesters and police in Mong Kok early this morning, after a day which saw significant progress on attempts to bring students and the government round the table to thrash out a solution to bring three weeks of street protests to an end. The fresh trouble is understood to have followed an online call "to take the junction of Argyle Street and Nathan Road after midnight", prompting scores of riot police to rush to the scene. Pepper spray was used at least once to disperse protesters. Officers used batons to hit out at protesters' umbrellas, according to witnesses at the scene. One protester said he saw plain-clothes policemen lashing out at protesters themselves. "I saw officers hitting protesters with batons. Several protesters suffered head injuries and were bleeding. They also dismantled supply stations," the protester, who gave his surname as Lo, said. One of the student protest leaders, Lester Shum from the Federation of Students, was present at Mong Kok to show support. He said that the demonstrators there were upholding the principles of civil disobedience and he didn't know why officers had charged at them. "We are not gangsters. Even if you beat us until we bleed, we will come back as we want genuine universal suffrage and civil nomination," said Shum. Watch: Injured protester: Hong Kong police officer hit me In a statement, police condemned protesters' actions, saying they had severely disrupted public order. "In the small hours of today, a large number of people who were illegally occupying the carriageway on Nathan Road near Argyle Street in Mong Kok suddenly attempted to charge police cordon lines by pulling the mill barriers thereat and shoving police officers. Police then gave warnings to them repeatedly, including displaying warning banners, to urge them to stop charging police, but was ignored," the statement read. "Police thus took resolute action by applying minimum force to disperse them to prevent the situation from deteriorating. After putting back the mill barriers at scene, police returned to the original cordon lines. Police did not carry out clearance." The statement said one man was arrested after he was allegedly found with two knives in his backpack. Three protesters were reported to have been injured and a police officer suffered from a dislocated shoulder, it added. Meanwhile RTHK reported that a man had been arrested in Tin Shui Wan on Saturday night on suspicion of encouraging people over the internet to take part in illegal assemblies in Admiralty and Mong Kok and to charge at police. The latest disturbances came as talks aimed at ending the increasingly violent confrontations over the city's electoral future looked set to go ahead. Government and mainstream pro-democracy movement leaders united in condemnation of violent clashes between police and protesters. Watch: Violent clashes in Mong Kok lead to arrests and injuries overnight In what appeared to be a concerted attempt to stop an escalation of street confrontations and isolate radical protesters ahead of Tuesday's talks, government No 2 Carrie Lam Cheng Yuet-ngor, the Executive Council and pro-government groups condemned violent clashes on Saturday in Mong Kok. Their call was echoed by Occupy Central co-founder Dr Chan Kin-man and student leader Lester Shum, who both said talks and non-violence should be the only way forward. Police commissioner Andy Tsang Wai-hung - who has been absent from public view during the past three weeks of turmoil - also delivered a stern warning over what he described as actions that were "hurting Hong Kong and hurting our society". Shum's call for non-violent protest - in which he also agreed talks should be within the framework of the Basic Law - came with a caveat that it was the hardline August 31 decision by the National People's Congress on elections that had kept people on the streets. "We are afraid the [Chief Executive] C. Y. Leung camp will try to sabotage the chances of dialogue, and so we need to hold fast to non-violence, which is our biggest strength," he said. Thirty-three people aged 20 to 66 were arrested after clashes in Mong Kok and Lung Wo Road in Admiralty early on Saturday. READ MORE: Protesters form new blockades in Mong Kok after night of chaotic clashes with police Interactive map: Current barricades in Mong Kok Legislative Council president Jasper Tsang Yok-sing said most peaceful demonstrators would not agree to violence. "It [the violence] definitely exceeds the limit of civil disobedience. I can't see they are conveying any messages. It should not happen." Forty-one pro-establishment legislators issued a joint statement criticising Saturday's clashes, in which more than 10 police officers and an unknown number of protesters were injured. In an article in Chinese-language newspaper Ming Pao yesterday, Occupy's Chan called on protesters and police to show restraint. Chan also reiterated that the three Occupy Central organisers and pan-democrats would turn themselves in when the movement ends. Meanwhile, students were preparing for the two-hour meeting with five government officials at the Hong Kong Academy of Medicine. Professor Leonard Cheng Kwok-hon, president of Lingnan University and an ex-adviser to Leung Chun-ying's election campaign, will moderate.