According to CNBC, Mr Paddock was a resident of Mesquite, Nevada, with no known terror connections.
Police have confirmed the identity of the killer, while US media is reporting he was a white male who had been living in a retirement community.
The gunman was shot dead by authorities after he opened fire on the concert, killing more than 50 people and injuring over 200 others.
Authorities “located numerous firearms” in Paddock’s hotel room as investigations into the incident continue.
The incident has been confirmed as the deadliest mass shooting in US history.
Updating reporters on the incident, Joseph Lombardo, the sheriff of the Las Vegas Metropolitan police department, said: “There was a shooter on the 32nd floor. Officers responded and engaged a suspect at that location. He is dead currently. He is a local resident.”
Police are also believed to have located Marilou Danley, a woman who travelled with the shooter and is thought to have been his roommate.
According to police files, Ms Danley is 62 years old.
On her Facebook profile, Ms Danley describes herself as “proud mum and grandma who lives life to the fullest.”
Mr Lombardo also confirmed that one of the police officers shot dead at the concert was a member of the Las Vegas Police Department (LVPD), while another remains in a critical condition.
Panicked concertgoers fled the scene as Mr Paddock shot at the 40,000-strong crowd for several minutes, with authorities scrambling to locate and kill the gunman.
Meanwhile, a witness was reportedly warned that everyone at the Route 91 music festival was “going to die” just 45 minutes before the attack near the Mandalay Bay hotel.
Chilling video has emerged showing the moment gunshots ring out during the busy music festival, cutting short Jason Aldean’s appearance as the packed out audience escaped the shooter in terror.
One woman, who was at the Route 91 music event, claimed an unidentified woman had told other concert-goers they were “all going to die” after pushing her way to the front of the venue.
The witness, 21, told local news: “She had been messing with a lady in front of her and telling her she was going to die, that we were all going to die.
“They escorted her out to make her stop messing around with all the other people, but none of us knew it was going to be serious.”
She described the lady as Hispanic and was escorted from the venue along with a man.
The unnamed witness, who was attending the event on her 21st birthday, described the pair as short, both around 5 ft 5ins to 5ft 6ins tall, and looked like “everyday people”.