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Q: But  Clark County Sheriff Joseph Lombardo  told reporters  he  found it hard to believe that the arsenal of weapons  ammunition and explosives recovered by police in their investigation could have been assembled by Paddock completely on  his  own.
âYou have to make an assumption that  he  had some help at some point â  Lombardo  said at a news briefing.  Lombardo  said the attack was the obvious outcome of meticulous planning.
âWhat we know is that Stephen Paddock is a man who spent decades acquiring weapons and ammo and living a secret life  much of which will never be fully understood â  the sheriff  said.
In response to a question   Lombardo  said investigators were examining the possibility Paddockâs purchase of more than 30 guns in October 2016 may have been precipitated by some triggering event in  his  life.  He  did not elaborate.
âWeâve had a couple good leads and weâre working our way through it â Sheriff Joseph Lombardo told the president.
A: 
Las Vegas gunman's girlfriend says no advance knowledge of massacre