In early October, Islamic hackers tried to make good on their threat to take down a Vatican web site. Attempts to hack into and deface the Vatican web site were defeated. The Islamic hackers also tried a DDOS (Distributed Denial of Service) attack. Normally, this can shut down a site with a flood of garbage messages, generated from thousands of "zombie PCs" (machines hackers have earlier seized control of). To their credit, the system administrators of the Vatican site were able to defeat the DDOS attack and keep the site operational. The Islamic hackers, who made their threat openly on an Internet forum, were upset at Pope Benedict's criticism of Islam in his Regensburg speech. Other Moslems, in response to the pope's remarks, murdered a nun in Somalia, and burned down several churches else where. Pope Benedict had quoted a medieval comment about Islam being a violent religion.