New disclosure shows a casino guard alerted hotel to gunman before Vegas massacre began. So why did it take so long to stop him?

Before the Las Vegas massacre began, a wounded Mandalay Bay hotel security guard called hotel officials to warn them about a gunman on the 32nd floor, an investigator told the Los Angeles Times on Tuesday.

But police did not arrive at the room where the guard had been shot until after Stephen Paddock had finished a 10-minute shooting rampage on a crowd gathered below for a country music festival, the investigation now shows.

The revelation that hotel security had been alerted comes a day after Las Vegas police changed their timeline of how the Route 91 Harvest country music festival massacre started on Oct. 1 — not with an attack on a crowd along the Strip at 10:05 p.m., but with the shooting of Mandalay Bay security guard Jesus Campos inside the hotel about six minutes before.

“He called it in before” the attack began, possibly using a hallway phone to contact hotel security, Clark County Assistant Sheriff Tom Roberts told The Times in an interview. “He manually called down and he used his radio to call. … That’s what we were briefed this morning.”

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