BANGKOK , Thailand ( CNN ) -- Riot police descended on scores of anti-government protesters in the streets of Thailand 's capital as violence intensified early Monday . Thai soldiers secure an area early Monday in Bangkok after dispersing protesters . Protesters took over two gas tanker trucks in one Bangkok intersection , ramping up the intensity of the ongoing conflict . `` We 're at a freeway intersection and they 've commandeered two gas tankers that they are threatening to blow up , '' CNN Correspondent Dan Rivers reported from the scene . Protesters elsewhere lit fires in the streets , blocked intersections and surrounded the prime minister 's office , where there was no sign of security . Rivers said protesters had slashed the tires of a police van . Video from the scene showed shield-wielding riot police clashing with protesters , and at times people were carried away on stretchers . There were no immediate figures on deaths or injuries . `` What they 're trying to do is face down the government , which so far has appeared -- it must be said -- very weak and unwilling to order the police or the army to use much force , '' Rivers said . `` That was , until a few hours ago where .. they have started to crack down on this movement . '' Earlier , Thai Prime Minister Abhisit Vejjajiva announced a state of emergency Sunday in the capital and surrounding areas in an attempt to tamp down days of heightening protests . Thousands of `` red shirt '' protesters have rallied for days to demand Abhisit 's resignation . The red shirts have given the prime minister repeated deadlines to resign , but those have come and gone . The protesters are loyal to former Prime Minister Thaksin Shinawatra , who was ousted in a 2006 coup . They have said Abhisit 's government was not democratically elected and want him to resign and schedule elections . iReport.com : `` Red shirts '' take to streets . Abhisit , who has held the position for four months , has rejected calls to step down . Meanwhile , Thaksin , in a video-link speech from an unknown location , urged his supporters to revolt , according to a report MCOT , a public company run under the supervision of the Thai prime minister 's office . Thaksin said he would return to Thailand to lead people in a march on the capital if necessary , according to the report . Immediately after Abhisit 's state-of-emergency declaration , dozens of protesters stormed the country 's Interior Ministry and pelted Abhisit 's car with rocks , chairs , flags and sticks as he escaped . Protesters climbed atop two military armored cars after laying down on the road and blocking its path . A police officer was led away by demonstrators and beaten , said Sathit Wongnongtoey , an official in the prime minister 's office . The emergency measure will allow officials to arrest and detain protesters without a court order , and to restrict gatherings , authorities said . iReport.com : `` Numerous buses set ablaze '' Also Sunday , police arrested a leader of the red shirt movement -- named for the color of their demonstrators ' attire . The leader , Arismun Pongruengrong , was charged with inciting people to break the law , police said . Arismun led demonstrators who forced their way into a hotel Saturday where Asian leaders were to meet . The action prompted the indefinite postponement of the Association of South East Asian Nations ( ASEAN ) summit in the southern coastal city of Pattaya . CNN 's Kocha Olarn contributed to this report .
NEW : Shield-wielding riot police clash with protesters early Monday morning . PM declares state of emergency in Bangkok and surrounding area . Protesters storm the country 's interior ministry and attack PM 's car .