For over a month. Indonesia was in crisis. Forest fires raged out of control as the country Suffered its worst drought for 50 years . Smoke form the fires mixed with sunlight and hot dry air to form a cloud of smog This pollution quickly spread and within days it was hanging over neighbouring countries including Malaysia．Singapore and Thailand When the smoke combined with pollution from factories and cars．it soon became poisonous(有毒的)．Dangerous amounts of CO became trapped under the smog and pollution levels rose．