While the investigations into the Las Vegas shooting have revealed little about the motive behind the killings, federal investigators once again searched gunman Stephen Craig Paddock's three-bedroom house in Mesquite, Nevada, on Sunday, October 8.

The search comes exactly a week after Paddock gunned down 58 people and injured over 500 from the 32nd floor of the Mandalay Bay hotel on October 1. His house was first searched on Monday, October 2. Explaining why the investigators had returned to Paddock's house, local police Chief Troy Tanner, who accompanied FBI agents, told the Associated Press that it was for "re-documenting and rechecking."

"I don't think they are after anything specific," Tanner noted. "They're going through everything and photographing everything again."

Meanwhile, the authorities who first entered Paddock's room in the hotel said that the place looked like "an armory." They also found a note on the nightstand that had various calculations through which the gunman wanted to maximise the number of victims.

Talking about what the room looked like, Dave Newton, an officer with the Las Vegas Metropolitan Police Department's K9 unit, told CBS' "60 Minutes:" "An armory. So many guns, so many magazines, stacks and stacks of magazines everywhere just in suitcases all neatly stacked against pillars that were in the room, all stacked up, rifles placed all throughout."

Newton explained that the room had so many monitors and electrical equipment that it looked like "almost a gun store."

Las Vegas shooting
Police continue to keep a section of Las Vegas Boulevard closed as they work the crime scene following a mass shootingReuters

Meanwhile, the fact that Paddock had made numerous calculations to maximise the number of target was also revealed by various other officials in the past week.

"I did notice a note on the nightstand near his shooting platform. I could see on it he had written the distance, the elevation he was on, the drop of what his bullet was going to be for the crowd," Newton said. "So he had had that written down and figured out so he would know where to shoot to hit his targets from there."

Further explaining that Paddock must have taken days to figure out all the details and plan the attack in such a meticulous way, Sgt. Joshua Bitkso also told 60 minutes that the 64-year-old gunman had made extensive efforts to study even the hotel's surveillance systems.

"He had toolboxes [and] power tools to run wires for his surveillance systems. For everything that he had, it took him days to finish," Bitkso noted.

Amid the investigations, it has also been said that the gunman was seen with a mystery woman before the massacre. It is now being said that this woman, who was seen with Paddock a few days before the attack, was a prostitute and investigators are now interviewing numerous other call-girls in the area for clues, reported the Associated Press.

Stephen Paddock
Stephen Paddock, 64, the gunman who attacked the Route 91 Harvest music festival in a mass shooting in Las Vegas, is seen in an undated social media photoReuters

The officials are also baffled by the fact that Paddock has left behind no information on the reason behind the shooting, whereas such killers usually leave behind notes or at least post cryptic messages on social media.

Apart from frequenting casinos, Paddock was also a regular in cruises and took about 20 trips to various foreign ports. A lot of these ports are said to have been in Europe and the Middle East – mostly Spain, Italy, Greece, and the UAE, reported CNN. This link too is now being investigated.

The investigators have also gotten in touch with Paddock's girlfriend Danley who said that she had no idea of the gunman's plans. She had earlier been named as a "person of interest," but it was later reported that the police believed she didn't have a hand in the attack as she was out of the country on that fateful day.