It is now the worst mass shooting in modern US history but it was hard to make sense of the event as it unfolded in Las Vegas.
Thousands of panicked fans at a music festival scrambled to save their lives as a gunman opened fire and sprayed hundreds of bullets into the crowd.
What was once dubbed one of the most fun places on Earth is now the stage of some of the most horrid mass killings in modern history, with 58 people dead and hundreds of victims in hospital.
When police first responded to the incident, the chaos made it hard to discern what was happening. Las Vegas turned to absolute chaos in a matter of seconds, as police scanner traffic shows.
Police dispatchers were flooded with calls reporting gunfire at the Route 91 Harvest country music festival.
By the time police reached the shooter, holed up in room 135 on the 32nd floor of the Mandalay Bay Resort & Casino (close to the famous "Welcome to Las Vegas" sign), Stephen Paddock, responsible for killing dozens, had taken his own life too.
Police found his body along with a cache of at least 19 weapons, more than an hour after he opened fire.
Here's a timeline of what we know so far, based on police audio:
10.08pm: Stephen Paddock opens fire.
10.14pm: An officer reports that he is in the Mandalay on the 31st floor and can hear automatic gunfire from "one floor above us."
10.17pm: Updates flood in on wounded victims. "We can't worry about victims. We need to stop the shooter before we have more victims. Anybody have eyes on the shooter?" an officer asks over the radio.
"We have multiple, multiple victims. Shots fired right outside the medical tent. We got one shot in the head," an officer says.
Another police officer responds via radio: "Hey officers, please stay calm. We're trying to get this set up. OK. Just stay calm."
10.18pm: Officers ask the hotel to shut down the elevator in the Mandalay Bay Hotel & Casino so the suspect cannot leave.
10.21pm.: An out-of-breath officer yells over the radio: "Gunshot wounds to the chest and head. We need immediate medical!"
Officers say they are still taking fire from a very high floor in the hotel. "Every officer who comes up is going to be a target if they're driving on Las Vegas Boulevard."
10.23pm: Dispatchers start receiving false reports from witnesses saying there could have been three shooters.
10.44pm: Reports of concertgoers taking police cars that were parked near the venue. "I need some more units here. I'm being overtaken by citizens trying to take patrol cars."
10.57pm: Police lock down the hallway near room 135.
What followed were 20 minutes of chaos with multiple false reports of additional shootings and a potential bomb threat at one of the neighbouring casinos. Officers worry these are just distracting manoeuvres but send teams to check out potential threats.
11.24pm: Officers start clearing the room and whisper over the radio, "We have one suspect down."
11.28pm: "We have one suspect down. Multiple firearms," an officer says over the radio, an hour and 20 minutes after the attack began. He says this was definitely the suspect who was "firing into the crowd".