The latest details to emerge regarding the deadly Las Vegas mass shooting earlier this month indicate the first gunshot came minutes earlier than previously reported.

According to CNN, gunman Stephen Paddock shot a security guard at the Mandalay Bay Resort and Casino about six minutes before a hail of bullets rained down on a country music concert across the street.

Clark County Sheriff Joseph Lombardo revealed the update, saying Jesus Campos was shot in the leg just before 10 p.m. on Oct. 1. At 10:05 p.m., the shooting began that left dozens dead and hundreds injured in what is being described as the deadliest mass shooting in modern U.S. history.

“What we have learned is Mr. Campos was encountered by the suspect prior to his shooting to the outside world,” Lombardo explained.

Earlier reports speculated Campos was killed after the attack, just prior to Paddock killing himself in his room on the 32nd floor of the hotel.

As CBS reported last week, officials sang Campos’ praises for providing information to police even after sustaining a gunshot wound.

Undersheriff Kevin McMahill called Campos “a true hero” in a Friday press conference.

“We now know that he was dispatched to a door alarm on the 32nd floor,” he said. “He went up there to investigate the open door, and as he was doing his job, he came under fire by our suspect.”

The latest update still indicates Paddock shot Campos when the security guard reported to the floor in response to a report of an open door.

As Heavy reported, Lombardo was not willing to make the “assumption” that Campos’ presence on the 32nd floor that night in any way sped up Paddock’s deadly plans.

Lombardo provided additional details, including the fact that investigators have still not found any evidence suggesting another shooter was involved.

[Featured image: Associated Press]