A hotel worker reportedly said Wednesday that he told hotel dispatchers to call police about a gunman in the Mandalay Bay Resort and Casino before the shooter began firing his weapon on a crowd of people in Las Vegas, according to CBS News.

The maintenance worker, Stephen Shuck, said he heard gunshots while investigating a jammed door on the 32nd floor, the same floor where shooter Stephen Paddock fired upon a crowd of more than 20,000 people, killing 58 and injuring more than 500 others.

Shuck said a hotel security guard advised him to get down and take over.

"It was kind of relentless so I called over the radio what was going on," Shuck said on Wednesday, according to CBS. "As soon as the shooting stopped we made our way down the hallway and took cover again and then the shooting started again."

Shuck’s timeline of events fits with what police said on Monday. Authorities revised the timeline of the events of the events in Las Vegas, saying that a hotel security guard was shot six minutes before Paddock fired on the crowd of people, as CNN reported.

This new timeline of events differs from the original timeline, which suggested that Paddock had shot the security guard, Jorge Campos, after the shooting finished.

Joseph Giacalone, a professor at John Jay College of Criminal Justice and a retired New York City police sergeant, told CBS that the new timeline “changes everything.”

Still, the hotel remains unsure about the new timeline, according to CBS.

"We cannot be certain about the most recent timeline," said Debra DeShong, a spokeswoman for MGM Resorts International. "We believe what is currently being expressed may not be accurate. This remains an ongoing investigation with a lot of moving parts."

Hotel operators have worked to increase security. As The Las Vegas Review-Journal reported, hotels and casinos are investigating “Do Not Disturb” signs to better facilitate security of guests.

Wynn Resorts CEO Steve Wynn told Fox News that his hotels will begin investigating rooms that have a “Do Not Disturb” sign on their doorknob for more than 12 hours.

“The scenario that we’re aware of … indicated that (the shooter) didn’t let anyone in the room for two or three days,” he said. “That would have triggered a whole bunch of alarms here.”