Terrorist activity increased dramatically in 2003, with the Riyadh compound bombings and other attacks, which prompted the government to take much more stringent action against terrorism.[11] Suicide bombers killed 35 people at housing compounds for Westerners in Riyadh hours before U.S. Secretary of State Colin Powell flew in for planned visit in May 2003. More than 300 Saudi intellectuals - women as well as men - signed a petition in September 2003, calling for far-reaching political reforms. A month later, police had to break up an unprecedented rally in the centre of Riyadh calling for political reform.