Lewis, argue that terrorist organizations like Al-Qaeda might use cyber attacks to disrupt emergency services in order to reinforce and multiply the effect of a physical attack. Conventional firearms Despite the popular image of terrorism as bombings alone, and the large number of casualties and higher media impact associated with bombings, conventional firearms are as much if not more pervasive in their use. For example, in the second part of the 2011 Norway attacks, 69 people were killed by Anders Behring Breivik, a man armed with two guns. The 2008 Mumbai terrorist attacks were done partly by guns and partly by bombs. Also, one Transportation Security Administration officer was killed and few others injured by a man with an assault rifle in the 2013 Los Angeles International Airport shooting. In 2016, Omar Mateen killed 49 people with firearms during Orlando nightclub shooting. In 2004, the European Council recognized the "need to ensure terrorist organisations and groups are starved of the components of their trade," including “the need to ensure greater security of firearms, explosives, bomb-making equipment and technologies that contribute to the perpetration of terrorist outrages." Stabbing Stabbing attacks are inexpensive and easy to carry out, but very difficult for security services to prevent. Secondary attacks Terrorist groups may arrange for secondary devices to detonate at a slightly later time in order to kill emergency-response personnel attempting to attend to the dead and wounded. Repeated or suspected use of secondary devices can also delay emergency response out of concern that such devices may exist. Examples include a (failed) device that was meant to release cyanide-gas during the February 26, 1993 World Trade Center bombing; and a second car bomb that detonated 20 minutes after the December 1, 2001 Ben Yehuda Street Bombing by Hamas in Jerusalem. Training There are and have been training camps for terrorists. The range of training depends greatly on the level of support the terrorist organization receives from various organizations and states. In nearly every case the training incorporates the philosophy and agenda of the group's leadership as justification for the training as well as the potential acts of terrorism which may be committed. State sanctioned training is by far the most extensive and thorough, often employing professional soldiers and covert operatives of the supporting state. Cover Where terrorism occurs in the context of open warfare or insurgency, its perpetrators may shelter behind a section of