Media playback is unsupported on your device Media caption The BBC's Daniel Sandford described a scene of "serious devastation" in Kiev 
 
 Ukraine's President Viktor Yanukovych has agreed to negotiate with pro-EU protesters and opposition leaders after violent clashes in the capital Kiev. 
 
 He said a cross-party commission would be set up on Monday to try to resolve the deepening crisis. Opposition leaders confirmed this. 
 
 Earlier, a group of protesters - trying to reach parliament - clashed with police. Dozens of people were injured. 
 
 The US and EU called for an end to the violence and urgent political talks. 
 
 The violence broke out as many thousands of protesters held a rally in Kiev's Independence Square, outraged by new laws which they said restricted basic freedoms. 
 
 The ruling party of Mr Yanukovych denies this, saying the legislature is in line with European standards. 
 
 However, Western countries have expressed deep concern at the new laws. 
 
 The anti-government movement began in protest at Mr Yanukovych's decision in late November to pull out of a landmark treaty with the EU, but has expanded to demand his resignation. 
 
 'Civil war' warning 
 
 Late on Sunday, President Yanukovych's press office said a "working group" headed by National Security and Defence Secretary Andriy Kluyev would be set up. 
 
 Image copyright Reuters Image caption Some in the crowd of protesters attacked a bus being used by the police as a cordon 
 
 Image copyright Reuters Image caption It was set alight after petrol bombs were thrown 
 
 Image copyright Reuters Image caption Opposition leader Vitaly Klitschko (centre), who called for calm, was sprayed with a powder fire extinguisher 
 
 It said the group - made of members of government and the presidential administration - would meet opposition representatives on Monday to try resolve the crisis. 
 
 Opposition leader Vitali Klitschko confirmed this after meeting President Yanukovych at his residence outside Kiev. 
 
 "We must use every opportunity to resolve the crisis peacefully," the former world heavyweight boxing champion, who leads the Udar party, told Ukraine's Hromadske TV. 
 
 He warned against a "scenario of force", adding that he "didn't rule out the possibility of a civil war". 
 
 Arseniy Yatseniuk, another opposition leader, said Mr Yanukovych personally called him to say that he was ready for talks. 
 
 Media playback is unsupported on your device Media caption The BBC's Daniel Sandford in Kiev said there were 'waves' of attacks 
 
 However, the opposition warned that the talks must produce real results and not be an opportunity for the president to play for time. The opposition is demanding the resignation of the government and snap presidential elections. 
 
 But opposition leaders are under huge pressure to come up with an action plan, amid criticism from many activists that their campaign has been too passive. 
 
 'Provocateurs and extremists' 
 
 Sunday's rally in Kiev, attended by many thousands, began with calls from opposition politicians to disregard the new laws curbing protests that pro-EU demonstrators have been staging for the past two months. 
 
 But clashes erupted as a group of demonstrators - reportedly far-right activists - headed away from the main square towards parliament to express their outrage. 
 
 They ran into police and interior troops cordons near the Dynamo football stadium, some 300 metres from Independence Square. 
 
 The demonstrators pelted police with flares, thunder flashes and petrol bombs, the BBC's Daniel Sandford in Kiev reports. 
 
 They overturned a bus used by police and set it alight. Other vehicles were also set on fire. 
 
 Police - who were sheltering behind buses under their riot shields - threw their own thunder flashes and gas canisters to try to force the crowd back. 
 
 Hours after darkness fell, the stand-off was continuing on Hrushevskyy Street, some 100 metres from Independence Square. 
 
 Police also used water cannon to try to disperse the demonstrators. 
 
 Interior ministry spokesman Serhiy Burlakov blamed "provocateurs and extremists" for the confrontations and urged people not to follow their lead. 
 
 Media playback is unsupported on your device Media caption Some protesters broke up paving stones to use as missiles 
 
 Police were filming everything and had opened criminal proceedings under Article 294 (organisation of mass riots), the interior ministry said. 
 
 The opposition leaders said they were committed to a peaceful resolution of the crisis, denouncing those activists who took part in clashes. 
 
 'Enslaving' laws 
 
 During the day, the rally on the main square heard a call from a former Ukrainian navy chief for members of the armed forces to defy "illegal" orders from those in power, Unian news agency reported. 
 
 "Tomorrow the regime will enslave you too. Therefore we are calling on you to fulfil your military oath of loyalty to the Ukrainian people and not to the authorities who have gone off the rails," said Rear Admiral Ihor Tenyukh, who was sacked by Mr Yanukovych in 2010. 
 
 The new curbs on protests, which have been signed into law by the president, include: 
 
 A ban on the unauthorised installation of tents, stages or amplifiers in public places 
 
 Provision to arrest protesters wearing masks or helmets 
 
 A ban on protests involving more than five vehicles in convoy 
 
 Hefty fines or jail for breaches of law 
 
 The protesters have been camping out behind extensive barricades on the Euromaidan, as Independence Square has been dubbed. ||||| KIEV, Ukraine (AP) — Protesters erected barricades from charred vehicles in central Kiev as the sound of stun grenades pierce the freezing air, after a night of rioting sparked by passage of laws aims at curbing street protests. 
 
 Protesters throw stones during clashes with police, in central Kiev, Ukraine, early Monday, Jan. 20, 2014. Anti-government protests in Ukraine's capital escalated into fiery street battles with police... (Associated Press) 
 
 Protesters prepare to clash with riot police in central Kiev, Ukraine, Sunday, Jan. 19, 2014. Anti-government protests in Ukraine's capital escalated into fiery street battles with police Sunday as thousands... (Associated Press) 
 
 Opposition leader and former WBC heavyweight boxing champion Vitali Klitschko, right, is attacked and sprayed with a fire extinguisher as he tries to stop clashes between police and protesters in central... (Associated Press) 
 
 A protester throws a molotov cocktail towards a burning police car, in front of him, during clashes with police, in central Kiev, Ukraine, early Monday, Jan. 20, 2014. Anti-government protests in Ukraine's... (Associated Press) 
 
 Protesters clash with riot police in central Kiev, Ukraine, Sunday, Jan. 19, 2014. Anti-government protests in Ukraine's capital escalated into fiery street battles with police Sunday as thousands of... (Associated Press) 
 
 Protesters clash with police in central Kiev, Ukraine, early Monday, Jan. 20, 2014. Anti-government protests in Ukraine's capital escalated into fiery street battles with police Sunday as thousands of... (Associated Press) 
 
 Dozens of protesters remain camped out on a central street in Kiev on Monday, as some vehicles torched by protesters overnight continue to blaze. 
 
 A large demonstration against anti-protest laws turned violent Sunday, when hundreds of radical protesters broke off from the main peaceful rally and marched toward the parliament building. They began attacking rows of police with sticks, stones and fire bombs, setting police vehicles on fire. Police responded with tear gas and water cannons. Dozens of protesters and police were injured. 
 
 The government is set to hold talks with leaders of the opposition Monday. ||||| MOSCOW — A large rally in Kiev, Ukraine, that was called in part to protest a new set of laws cracking down on public protests turned violent on Sunday when men in balaclavas attacked the police with sticks and threw firecrackers and cobblestones at them. 
 
 The police responded with tear gas. By early evening, at least one police van was burning on a central street in the city, and witnesses said people had been injured, though it was unclear how severely. 
 
 The violence appeared to be the worst in at least a month for the continuing protest movement in Ukraine, and it signified a deepening of the political crisis in the country, the most populous former Soviet state beside Russia. 
 
 Protests began in November, after the government of President Viktor F. Yanukovich declined to sign a sweeping free-trade agreement with the European Union. He later negotiated a financial aid package from Russia. 
 
 The fighting broke out on a side street leading to the Verkhovnaya Rada, or Parliament, and near Independence Square, which has been the center of the protests. 
 
 Photo 
 
 In speeches on the square, opposition leaders denounced the participants in the melee as provocateurs and said they did not represent the aspirations of the peaceful protesters. But the leaders were also powerless to stop the fighting. 
 
 By midnight, the streets were a scene of utter mayhem. Those fighting the police struck them with lengths of pipes and sticks, and hurled cobblestones the size of soccer balls into their midst. They sent fireworks whistling and sparking into their ranks, and threw what appeared to be firebombs, blossoming into flames when they struck. The police stumbled backward, patting at their clothes as fire burned their metal shields. 
 
 The riot police sprayed from a water cannon, in spite of the freezing temperatures. Gazeta.ru, a Russian news portal, reported that 70 police officers were wounded and 40 hospitalized. 
 
 The rally against the new laws enacted on Thursday drew tens of thousands of people, a smaller crowd than at the peak of the protest movement in December but larger than on recent weekends. Since November, protesters have occupied the square and several buildings, including City Hall. 
 
 Photo 
 
 Protesters said they were angered by laws seen as circumscribing the rights of public assembly. 
 
 The laws stiffened the penalties for setting up tents and stages in public spaces. They banned wearing helmets and balaclavas, a tactic of the opposition activists to protect themselves against the police, identification or arrest. 
 
 In defiance, many demonstrators showed up wearing upside-down kitchen kettles on their heads. 
 
 The movement’s leaders have struggled to formulate a response to the laws. 
 
 Photo 
 
 Arseniy P. Yatsenyuk, one of the main protest organizers, announced a plan to form a shadow Parliament, government and Kiev city administration that would operate under the laws of a 2004 Constitution that Mr. Yanukovich had amended — illegally, the opposition says. 
 
 Late Sunday, Mr. Yatsenyuk, speaking from the stage on the square, said he had received a call from Mr. Yanukovich saying the government was ready for negotiations. 
 
 Vitali Klitschko, the leader of Punch, a political party, and a former heavyweight boxing champion, told the crowd that he was “announcing a snap presidential election,” though the parliamentary opposition has no legal grounds to force a vote if Mr. Yanukovich does not resign. 
 
 This inability of the leaders to force political change under the current Constitution or consolidate around a single leader in spite of clear popular support for their antigovernment agenda in the capital became a precipitating cause of the violence on Sunday. 
 
 A leader of a group of protesters who arrived in a column of cars, a movement called Auto Maidan, after the name of the square, took the stage and said the opposition should choose one leader, and if it could not, the crowd should march on Parliament. 
 
 Mr. Yatsenyuk called this speech a provocation to violence. But some in the crowd acted anyway, moving toward Parliament and clashing with riot police officers. 
 
 After the fighting began, Mr. Yatsenyuk, speaking from the stage on the square, called on protesters to refrain from violence and denounced those who were fighting the police, saying they did not represent the opposition.
– Dozens of protesters and police were injured in Kiev clashes yesterday that came on the heels of new anti-protest laws, the AP reports; a Russian news site puts the number of wounded police at 70. The fighting continued into the night. Protesters used sticks and pipes, hurling large rocks, fireworks, and apparently firebombs at police, the New York Times reports. Police fired back with tear gas and water cannon. Though opposition leaders condemned the violence, they couldn't stop it, the Times notes. Following the clashes, Ukrainian president Viktor Yanukovich agreed to negotiations with opposition leaders and protesters, the BBC reports. Today, he said, a government "working group" would meet with opposition leaders and restore peace to the streets. Opposition head Vitali Klitschko, who met with the president, confirmed the plans. "We must use every opportunity to resolve the crisis peacefully," he said, noting the dangers of using force and saying he "didn't rule out the possibility of a civil war." Meanwhile, the unrest continues. Protesters have installed barricades against vehicles set alight, the AP reports, noting audible stun grenades.