Sirens ring out in the South Korean capital as Seoul hold a civil defence drill.<br/> <br />As part of a joint military exercise with the United States, areas of the capital came to a standstill as people practised what to do in an emergency.<br/> <br />Traffic stopped as people moved into safe places, such as train stations.<br/> <br />Underground in one subway, civilians and government officials learned CPR.<br/> <br />SOUNDBITE: JANG SUNG-GU, ACTION OFFICER OF CIVIL DEFENCE DIVISION AT SEOUL METROPOLITAN GOVERNMENT, SAYING (Korean):<br/> <br />"This exercise is a field for learning and exercising measures to deal with emergencies. This will teach our citizens how to escape safely or rescue injured people in time of emergency."<br/> <br />The annual exercise mobilizes thousands of U.S. and South Korean troops, focusing on defending South Korea in an emergency.<br/> <br />It comes amid tension between South Korea and its reclusive neighbour in the North.<br/> <br />North Korea has strongly denounced the drill, saying it preludes to war.
