LOS ANGELES (CBSLA) — Clark County Sheriff Joseph Lombardo said Monday that shooter Stephen Paddock shot a hotel security guard more than five minutes before the assault on concertgoers began.

“He was injured prior to the mass volley of shooting,” Lombardo said.

READ MORE: Strong Winds Cause Power Outages Across SoCal, Over 70,000 Residents Impacted

Previously, the security guard was credited with stopping the 10-minute assault by turning Paddock’s attention to him in the hotel hallway. But now that they know the security guard was shot before the attack, investigators now don’t know why Paddock stopped shooting.

Paddock could be seen in a 2011 incident at the Cosmopolitan Hotel, where he slipped and fell and later filed a lawsuit against that hotel. For the first time, we heard the gunman in his own words in a deposition obtained by CNN.

READ MORE: Shooting Outside Family Dollar Store In South LA

Paddock said he gambled all night and slept all day, sometimes wagering up to a million dollars a night at various Nevada casinos. He took Valium for anxiety. At one point, he calls himself the biggest video poker player in the world. The 64-year-old gunman has been described as “quirky” and a “narcissist.”  Officials say he meticulously planned the shooting. On 60 minutes, Las Vegas first responders said they were the first to arrive on the 32nd floor using the stairwell.

“He had screwed shut the door with a piece of metal and some screws … in the stairwell … going out to the hallway right by his door. Because he knew we’d be coming out that door to gain entry into his door so he tried to barricade it as best he could.”

Lombardo said they have no evidence to show there was a second shooter.

MORE NEWS: High Winds Topple Trees, Down Power Lines And Block Roads In Some Southland Neighborhoods

“We have no evidence or intelligence that the suspect was linked or had affiliation with any known terrorist groups or ideologies. In coordination with the FBI’s behavior analysis unit, a comprehensive picture is being drawn as to the suspect’s mental state.”