Eight days after Stephen Paddock shot nearly 500 people, killing at least 58 of them, investigators still don't have a motive, a "frustrated" Clark County Sheriff Joseph Lombardo told reporters on Monday. "This individual purposefully hid his actions leading up to this event, and it is difficult for us to find answers for those actions," he said, and discovering the motive is "our most important goal." Lombardo also disclosed that Paddock shot Mandalay Bay security guard Jose Campos six minutes before he opened fire, not three minutes after he stopped shooting. He said it would be premature to assume that wounding Campos sped up Paddock's mass shooting. Investigators do not know why he stopped firing after 10 minutes, or when he shot himself.

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