In August 1990, only two years after Baghdad and Tehran had agreed to cease hostilities, Iraqi forces invaded and occupied Kuwait. Saudi Arabia took action against Iraq, claiming Iraq's actions posed a serious threat to its security, and requested the United States and 32 other countries to bring troops into the kingdom. Riyadh's fears concerning Baghdad's ultimate intentions prompted Saudi Arabia to become involved directly in the war against Iraq during January and February 1991. The kingdom's air bases served as the main staging areas for aerial strikes against Iraqi targets, and for personnel of the Saudi Army who participated in both the bombing assaults and the ground offensive. Iraq responded by firing several Scud-B missiles at Riyadh and other Saudi towns. This conflict marked the first time since its invasion of Yemen in 1934 that Saudi Arabia had fought against another Arab state. Saudi and Coalition forces also repelled Iraqi forces when they breached the Kuwaiti-Saudi border in 1991 ( see Battle of Khafji).