Hong Kong police and pro-democracy protesters clashed in the early hours of Monday in some of the most violent skirmishes seen in recent weeks.<br /><br />Police baton-charged and pepper-sprayed thousands of demonstrators who had been trying to encircle government buildings.<br /><br />Two student groups heading the campaign for free elections for the territory’s next leader in 2017 have called on their supporters to escalate their action after two months of stalemate.<br /><br />The movement has threatened to become the biggest challenge to China’s Communist Party since its 1989 crackdown on pro-democracy protests in Tiananmen Square in Beijing.<br /><br />Meanwhile there has been a rise in tension between the UK and China over Hong Kong. A group of British MPs who were due to visit as part of an inquiry into relations between the UK and its former colony have been refused entry.