They arrive at the room and blow open double doors into it from the hall, only to find the suspect dead in a pool of blood in the darkened room - the blinds are all closed tightly - from an apparently self-inflicted gunshot wound. Guns are strewn around the room. They take note of the wires that web throughout the room, but relax when they see that they're linked to an elaborate camera system: they see one perched on a service cart outside the room, and another attached over the peephole.
"He has an intricate camera system set up," one of the first officers to arrive in the suite observes, "so he knew when officers were coming down the hallway."
The footage, seen publicly for the first time on Wednesday, was recorded on two body cameras worn by police officers who stormed the hotel suite of gunman Stephen Paddock, who killed 58 people and injured hundreds in the deadliest mass shooting in modern American history.
Its release is part of a cache of evidence to be made public after a judge sided with media organizations in a legal debate with the police. Police had sought to delay releasing the video footage and records, saying they were part of an ongoing investigation. Media organizations - including The Washington Post - argued in court that the department should have to make public recordings, 911 calls, affidavits and interview reports, among other things.
Paddock opened fire on a country music festival from his suite at the resort hotel in October, pumping bullets into a massive crowd that had gathered on the Las Vegas Strip. And when it was over, police say, Paddock turned one of his guns on himself.
The cameras capture the human moments of officers responding to what in a previous era might have been unthinkable: the massacre of concertgoers in a major American city inflicted by a lone man with no clear agenda, political or otherwise.
"How many did he put down, downstairs?" one officer, in a helmet and tactical gear, says to another during a lull after wiping his eye.
"A lot," the officer wearing the body camera responds.
Though police have released a preliminary report on the massacre, Paddock's motivation for the attack he planned meticulously remains an unsettling unknown. The Las Vegas police's preliminary report said that they still did not know why the gunman carried out the attack, although they ruled out any political or ideological radicalization. He acted alone, investigators said, and left behind no suicide note, manifesto or other explanation.
After some mass shootings, attackers make clear their reasoning, either in confessions to police or videotaped rants left behind. In other cases, answers remain elusive, leaving victims and their loved ones to struggle with explaining the horror unleashed upon them.
Authorities said the Las Vegas gunman had prepared carefully for the attack as well as the sprawling inquiry that would ensue, saying in court filings that he worked "to thwart the eventual law enforcement investigation." A search of the gunman's computers found an Internet search history that included queries for information about outdoor concert venues, SWAT tactics, weapons and the locations of various gun stores. Officials also said they found "numerous" images of child pornography on the gunman's computers.
Joseph Lombardo, the Las Vegas sheriff, has been critical of the fact that police have to release the body camera footage and other evidence. He said it would be onerous and difficult for the police department to handle the releases and described the footage as harmful to people who were injured in the massacre or lost loved ones.
"We believe the release of the graphic footage will further traumatize a wounded community. For that, we apologize," Lombardo told reporters during a news briefing Tuesday, during which he did not take questions. "Further victimization is certain to occur and is something we wanted to avoid."
After a district court judge in Clark County sided with the media outlets and said the records should be released, the Las Vegas police appealed to the Nevada Supreme Court. Last week, the court rejected that appeal.
Lombardo said detectives would have to be reassigned from their main duties to handle the release of the records, adding: "Many of our employees will have to endure reliving the incident."
The other materials will be made public "on a rolling basis," Lombardo said. He also said a final report on the police investigation would be published at an unspecified later date and "give context to the different documents that we have been ordered to release."
Days after the attack, police published harrowing recordings captured by officers' body cameras that showed the horror unfolding outside as the gunfire began.
Officers are seen scrambling to figure out where the shots were coming from. At one point, an officer is heard saying: "They're shooting right at us, guys. Stay down! Stay down!"
Images were also leaked that week offering glimpses both inside and outside the gunman's suite, a disclosure that Lombardo called troubling. When his department released its preliminary findings on the shooting earlier this year, that report included several photographs taken inside the suite. Among them were pictures of the guns stockpiled in the room and a chilling view that the gunman would have had of the concert venue while he fired.
Before Wednesday, the Las Vegas police had released some body-camera footage from the night of the shooting as well as photographs taken in the gunman's suite.
(This story has not been edited by NDTV staff and is auto-generated from a syndicated feed.)
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