New Information Changes Timeline of Las Vegas Shooting

Morning light reflects off the Mandalay Bay Hotel and the broken windows where shooter Stephen Paddock conducted his rampage from the 32nd floor in Las Vegas Nevada

Unlike so many other perpetrators of deadly mass shootings, Paddock left behind no suicide note, no manifesto, no recordings, and no messages on social media pointing to his intent, according to police.

Las Vegas police faced new questions on Tuesday about their response to this month's mass shooting after a county sheriff disclosed the gunman shot a security guard before, not after, opening fire on a crowd below his window at the Mandalay Bay hotel.

The exchange between the two reportedly took place about six minutes before Paddock sent a barrage of bullets into the crowd of concertgoers, killing 58 people and wounding hundreds more in what has become the deadliest mass shooting in modern USA history. Campos was shot in the leg, but survived, authorities said.

In an unusual bid to cast a wider net for additional tips, the Federal Bureau of Investigation and police have arranged with communications company Clear Channel to post billboards around Las Vegas urging members of the public to come forward with any information they believe might help investigators.

"He was injured prior to the mass volume shooting", Lombardo told reporters, announcing a new timeline to the shooting.

He added: "We want to make sure we are putting out the best information we have for everybody".

The gunman, Stephen Paddock, 64, shot from the windows of his 32nd-floor hotel suite into a crowd of 20,000 people attending an outdoor music festival on Sunday night, then killed himself before police stormed his room.

"Mr. Campos was encountered by the suspect prior to his shooting to the outside world", Lombardo said at a Monday news conference. "Mr. Campos prevented him from receiving any injuries", Lombardo added.

Paddock's girlfriend, Marilou Danley, continues to cooperate with police, McMahill and her lawyer, Matthew Lombard, said Saturday.

Protocol for Las Vegas hotels and casinos is to barricade the corridor where a shooting takes place and wait for police to arrive, said David Shepherd, a security expert who advises the Las Vegas Metropolitan Police Department and who ran the security team at The Venetian hotel on the Vegas Strip for eight years.

Officer David Newton of the Las Vegas Metropolitan Police Department, one of the first people to enter the Mandalay Bay Resort & Casino hotel room on October 1, spotted the note. Officials with MGM Resorts International, which owns the Mandalay Bay, declined to comment.

Mr McMahill acknowledged that the so-called Islamic State militant group had repeatedly said it was behind the attack, but said investigators had uncovered "no nexus" between that Mideast-based militant group and Paddock. "As I have conveyed to you from the very beginning, in your zest for information and my zest to ensure the public's safety and the calming of their minds, some things are going to change".

Lombardo's announcement also raises the question about why Paddock stopped firing during his rampage.

Although Campos had radioed for police to come after the exchange, police officers found him "in the hallway" as they rushed to the shooter's room, Lombardo said.

Police have not yet revealed a motive for the attack.

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