Taipei came to a brief standstill on Thursday when air raid sirens forced people off the streets and into nearby buildings or underground shelters in a rehearsal for a Chinese attack. The annual civilian drill is being held in cities across Taiwan this week, alongside military training, to prepare the self-ruled island for a potential Chinese invasion. "[The exercises] heighten everyone's vigilance, including the public's awareness," one retiree told AFP. "We can... figure out how to distribute finances and food, where to buy supplies, and where to access food." IMAGES AND SOUNDBITES