investigation las vegas massacre stephen paddock keep get strange since shoot massacre take live 59 injure hundreds others las vegas rt 91 country music festival see several timeline change lockdown las vegas coroner office strange protection around security guard mandalay bay casino resort include arm guard script appearance ellen show like well-known mass shooters stephen paddock hard drive miss abc news laptop computer recover las vegas hotel room stephen paddock launch deadly mass shoot u.s. history miss hard drive deprive investigators potential key source information kill maim many people abc news learned.paddock believe remove hard drive fatally shoot miss device yet recover source tell abc news.investigators dig paddock background also learn purchase software design erase file hard drive without hard drive examine impossible know ever use software one source said.the absence substantial digital clue leave investigators struggle piece together trigger paddock kill 58 innocent concertgoers injure 500 others oct. 1.did paddock remove hard drive something story connection evidence remove laptops cell phone suspect well-known mass shoot case america accord abc news dismiss curious evidence casual coincidence 2007 virginia tech shooter cho seung huiremoved hard drive computer dispose cell phone shortly massacre authorities even search pond miss digital media devices never recovered.the 2008 northern illinois shooter steven kazmierczak remove sim card phone hard drive laptop neither recovered.in 2012 sandy hook shooter adam lanza remove hard drive computer smash hammer screwdriver abc news report las vegas massacre suspect hard drive miss laptop