Las Vegas Gunman's Movements Days Before Massacre Revealed in Hotel Video

New surveillance video shows the movements of domestic terrorist Stephen Paddock inside the Las Vegas Mandalay Bay Resort and Casino in the days leading up to the Oct. 1 massacre that left 58 dead and hundreds injured.

In the Mandalay Bay security footage obtained by The New York Times, Paddock is seen leaving the hotel multiple times for his home in Mesquite — about 80 miles away — returning in a minivan filled with suitcases and chatting with bellhops as they stack the luggage on carts and help him transport it upstairs.

Over the course of seven days, Paddock reportedly transported 21 bags carrying the arsenal of weapons he used to carry out the attack.

In video, he is unassuming — riding the elevator, gambling, eating and tipping staff. The hotel's parent company, MGM, has previously said the multiple interactions Paddock had with staff were "normal in nature."

The video gives a more clear understanding of how Paddock was able to blend in among hotel guests while at the same time planning the deadliest mass shooting in modern U.S. history.

Authorities say Paddock opened fire on attendees of the Route 91 Harvest Festival from his 32nd-floor suite that night. He died of a self-inflicted gunshot wound to the mouth just before authorities stormed his room. His motive still remains a mystery.

According to autopsy reports obtained by the Las Vegas Review Journal last month, Paddock had anti-anxiety medication in his system at the time of his death.

While further autopsy results provide no clues into what contributed to Paddock's motives in the Route 91 Harvest Festival shooting, toxicology and brain examination found the 64-year-old had large amounts of nordiazepam, oxazepan and temazepan in his system, which are consistent with the anti-anxiety drug Valium. However, there was no evidence in the results of substances associated with alcohol.

Upon learning the results, Paddock's brother Eric told the Las Vegas Review Journal that there are "no physical excuses for what Steve did."

"We may never understand why Steve did this," Eric said.

Separate examinations on his brain conducted by researchers at Stanford University found no major abnormalities, nor evidence of Alzheimer's disease.

ABC News reported last fall that law enforcement officials discovered Paddock had severe mental illness that was likely undiagnosed.

Sources told the news agency that the portrait constructed from interviews with hundreds of people interviewed over the past week shows Paddock, though financially successful, had difficulty interacting with people. Described as standoff-ish and disconnected, he was a man who had difficulty establishing and maintaining meaningful relationships.