Insights into Las Vegas shooter's motive and behavior revealed in FBI documents.

Newly released FBI documents reveal that Stephen Paddock, the gunman who carried out the deadliest mass shooting in modern US history in Las Vegas in 2017, may have been resentful over how he and other high rollers were treated by casinos. The documents also provide a fuller picture of Paddock's obsessive gambling habits, but do not arrive at a definitive motive for his attack. One fellow gambler interviewed by investigators after the attack said Paddock had become angry about how casinos generally dealt with VIP players.