A dense smoke haze generated by the forest fire in Indonesia's Sumatra is shrouding cities in Singapore and Malaysia. Forest fires frequently break out in Indonesia during the dry season, most of which are caused by burning crop stalks left behind after the harvest, despite the ban on these issued by the government. Long-term forest fires have wreaked havoc on the ecological environment in Indonesia and a large amount of smoke is always blown into the neighboring countries -- namely Singapore and Malaysia -- by the monsoons. [Photo/Xinhua]