In July 1988, Iraqi aircraft dropped bombs on the Iranian Kurdish village of Zardan. Dozens of villages, such as Sardasht, and some larger towns, such as Marivan, Baneh and Saqqez, were once again attacked with poison gas, resulting in even heavier civilian casualties. On 3 July 1988, the USS "Vincennes" shot down Iran Air Flight 655, killing 290 passengers and crew. The lack of international sympathy disturbed the Iranian leadership, and they came to the conclusion that the United States was on the verge of waging a full-scale war against them, and that Iraq was on the verge of unleashing its entire chemical arsenal upon their cities.