Two Las Vegas security guards were fatally shot Saturday while investigating a disturbance in a room at a hotel-casino and the suspected shooter is facing critical injuries after turning the gun on himself, police said.

The gunman's motive wasn't known but investigators believe it was an isolated incident.

"I want you to know right now that this has nothing to do with terrorism," Capt. Robert Plummer told reporters outside the scene of the shooting.

The shooting happened before 7 a.m. at Arizona Charlie's Decatur, which is located west of the Las Vegas Strip. According to police, the suspect, Christopher Olague, ran from the hotel-casino after the shooting and into a nearby neighborhood where he tried to enter two homes but the residents were able to keep him out.

Police found him in a laundry room accessible through a garage of the second home after he appeared to have shot himself in the head, Lt. Dan McGrath said.

According to McGrath, Olague tried to enter the first home with the intention of stealing a car and also tried to take a vehicle on the street.

Police described Olague's condition as a "non-survivable wound."

The victims' identities were not released. Police said the uniformed security guards were a man and a woman in their 40s and that one was armed. Their identities and their causes of death will be released by Clark County Coroner's Office.

McGrath said the circumstances of what happened in the hotel room still unclear.

The hotel-casino's office did not immediately return a message seeking comment.

The shooting comes a day before law enforcement officers expect tens of thousands of New Year's Eve revelers on the Strip and three months after the city dealt with the deadliest mass shooting in modern U.S. history.

Officials have been trying to reassure residents and visitors that the city is safe, especially in the wake of the Oct. 1 shooting. A high-stakes gambler killed 58 people and injured hundreds more after he shattered the windows of his suite on the 32nd floor of the Mandalay Bay hotel-casino on the Strip and unleashed gunfire on a country music festival below. He then killed himself.