While terror seized the Vegas strip on Sunday night, authorities spent one hour and 12 minutes searching for Stephen Paddock, the "lone wolf" gunman who opened fire from the 32nd floor of the Mandalay Bay Resort and killed 58 people and injured 515 others.
In an NBC News segment from earlier today, NBC News Justice Correspondent Pete Williams hashed out the timeline from the first 911 call of shots fired to the minute police and the SWAT team breached Paddock's hotel room.
Williams said that the first 911 call came in at 10:08 p.m. "It took the police a while to figure out where the shots were coming from," he said. "They finally realized the shots were coming from the Mandalay Bay, but they didn't know what floor. So they start working their way up."
Williams went on to say that police started on the 29th floor of the hotel and worked their way up looking for Paddock. When they reached the 32nd floor, they immediately knew they were on the right floor — although it's unclear if they knew that from the smell or sound of gunfire.
"Then the police radio traffic picked up the sound of the police blowing the door off the room," Williams said.
In the audio, a SWAT member can be heard telling a dispatcher they had eyes on Paddock's door.
"We have sight on the suspect's door. I need everyone in the hallway to be aware of it and get back," the SWAT member said.
"All units on the 32nd floor, SWAT has explosive breach, everyone in the hallway needs to move back, all units move back," the dispatcher tells the officers.
The SWAT team can then be heard blowing the door off Paddock's room. Authorities entered Paddock's room to find him dead from a self-inflicted gunshot wound.
"So you hear the sound of that door being blown off and that happens at 11:20 p.m.," Williams said. "So it's one hour and 12 minutes from the time of the phone call until the police finally went in and found that Stephen Paddock had shot himself dead."
What's still unclear is how long Paddock was shooting during those 72 minutes while police were actively searching for him. Authorities reported an "excess of 10 rifles" in his hotel room.
Also unclear is Paddock's motive. While the Islamic State (ISIS) has claimed responsibility for the attack and says Paddock converted to Islam in recent months, U.S. officials say there is no concrete evidence linking him to the militant group.
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Photo Credit: Getty / Ethan Mill