Stephen Paddock rented multiple condos overlooking the annual Life Is Beautiful Festival, which this year was headlined by Lorde and Chance the Rapper, said the source, who is not directly involved in the investigation but has been briefed on its progress.

The source suggested that Paddock may have lost his nerve or simply changed his plans and checked into the Mandalay Bay Hotel on September 28. He then took a suite overlooking the Route 91 Harvest Festival and opened fire on an estimated 20,000 concertgoers below. Law enforcement recovered 23 weapons from the suite, including several rifles capable of automatic fire. Paddock concealed the arsenal in 10 suitcases, Joseph Lombardo, the sheriff of the Las Vegas Metropolitan Police Department told reporters.