The gunman responsible for Sunday's mass shooting in Las Vegas wired $100,000 to a bank account in the Philippines, his live-in girlfriend's home country, a week before carrying out the attack, it has been revealed.

Stephen Paddock, 64, sent the money to an account before setting up a sniper's nest on the 32nd floor of the Mandalay Bay hotel on Sunday.

Law enforcement officials who confirmed the wire transfer to NBC did not reveal who the bank account belongs to.

His live-in girlfriend Marilou Danley, 62, who was overseas while her boyfriend committed the worst mass murder in US history, is now on her way back to the US to face questions from the FBI.

On Tuesday, Las Vegas Sheriff Joseph Lombardo confirmed Danley is a person of interest in the investigation again.

Authorities appeared to rule her out on Monday as it emerged that she was not in Las Vegas at the time of the killing. They have since determined that she was travelling between Tokyo and the Philippines at the time and they now wish to speak to her.

'The investigation with her is ongoing and we anticipate some information from her shortly. This investigation has not ended with the demise of Mr. Paddock.

'I expect a substantial amount of information is to come in the next 48 hours,' Lombardo said on Tuesday.

Danley is understood to have told police that their romance began earlier this year.

Photographs obtained by DailyMail.com on Tuesday show them in the Philippines with her family in 2013 and in a Reno nightclub with the woman's hotel and casino colleagues in 2014.

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Stephen Paddock is pictured in an April 2013 photograph taken during a meal with his girlfriend Marilou Danley's family in the Philippines. Marilou, 62, is thought to be next to him, wearing a purple top

In the photographs, Paddock, is seen smiling and laughing with Danley's family during a 2013 trip to Manila.

Others show the couple partying with friends in Las Vegas in 2014 in a nightclub. Danley worked for hotels and casinos in Nevada.

In the family photographs, he is seen enjoying a traditional ‘Kamayan dinner’, which is eaten with your hands and comes from the filipino word for ‘hand’ - ‘kamay’.

Eating fish, vegetables and rice with his bare fingers, Paddock looks completely at ease with his companions, which also includes Danley’s sister Liza Werner, who’d travelled for the reunion from her home in Brisbane, Australia. Werner posted the pictures on Facebook with the words ‘Kamayan Blues.’

Danley is from the Philippines but also holds Australian citizenship and moved to the US following the death of her first husband more than 20 years ago, neighbors and friends have since revealed.

She was previously married to Arkansas resident Geary Danley and the pair were together for 22 years before separating in April 2013 - the same month she is pictured with Paddock in Manila.

She and Danley divorced the following February. She is understood to have arrived in the US with her daughter Sheila.

On Monday, Marilou's former step-daughters and her ex-husband said they were shocked by her association to Paddock who they claimed they'd never heard of before.

In the images the man appears happy and relaxed. What drove him to commit Sunday's massacre - the worst in US history - has not been established

Paddock was pictured talking animatedly with his girlfriend's relatives at the 2013 feast

'Our family doesn't know Stephen Paddock and has had no knowledge of Marilou's relationship with Mr Paddock.

'Marilou is our ex step-mom. She is a good and gentle person and I know she has to be devastated by what has happened,' Dionne Waltrip, one of her former step-daughters, told Arkansas station 5 News.

They did not reveal why she and their father parted ways, but reiterated that she was a 'good person'.

'We know nothing of this relationship ever. We have never heard of this man ever in our lives.

'She is kind. She's very gentle. She's very giving, she's always happy. She's just extremely nice and fun to be around.

'She's not harmful. She's not a bad person at all,' Deirdre Terrell, her other former step-daughter, said.

In another image believed to have been taken in Las Vegas in 2014, Paddock (circled) is seen with a large group in a nightclub. Danley is pictured second right

The first record of Marilou in the US is in 1992 and in Memphis, Tennessee. For 11 years, she lived in various houses there and carried out a brief stint in Arizona.

In 2003, records suggest that she moved to Nevada. She has been listed on the home where she lived with Paddock since January this year.

It is not clear how she met Paddock but it is likely through their mutual connection to the gambling world.

The 64-year-old was addicted to video poker, spending $10,000 a day on video games before his death.

Earlier today, Danley’s nephew Jordan Knights revealed that he’d gone to visit his auntie and Paddock in Las Vegas only a few weeks before the tragedy and had no inkling that Paddock was building up an arsenal of weapons, which would go onto kill 58 and injure 527 others who were attending the Route 91 Harvest Festival on Sunday night.

Knights was travelling in the US with his mother, Amelia Manango, Danley’s sister. She posted a picture of the MGM Grand entrance onto her Facebook on August 29.

'It seemed like he just looked after my aunty and that was it,'he told 9 News after the shooting on Monday.

When asked if there was any signs that he was into guns or mentally unstable, he responded: 'He didn't seem like he was the type of guy to do that. I didn’t even know he knew about guns.'

He then told The Courier-Mail that the pair went to family lunches at a casino, adding: 'He was a normal person pretty much. It’s just weird, crazy (what has happened). It’s hectic sh**.'

Knights went onto say there was no suggestion Paddock was a religious man.

He said Paddock was friendly towards him, adding: 'I wouldn’t have a clue (if he had been radicaliszed by Islam).

Paddock shot himself before a SWAT team could get into him inside his suite on the 32nd floor of the Mandalay Bay hotel on Sunday night.

Paddock (left in an undated photo) killed himself before a SWAT team could get to him on Sunday night. Marilou Danley, his girlfriend, was in the Philippines at the time. She will be questioned upon her return to the US on Wednesday

Marilou (above with her daughter Sheila and granddaughter) is expected to return to the US on Wednesday

The woman's former stepdaughters and ex-husband say she is a 'gentle' and 'kind' person. Marilou is understood to have come to the US in the early 1990s

It took them 72 minutes from when the first 911 call was placed to break into the room.

Marilou's was previously married to Arkansas resident Geary Danley (above) His family released a statement on Monday expressing sympathy for the victims and stating that he had never heard of Paddock

By the time they got in, Paddock, whose brother said had made 'millions' through real estate deals, had taken his own life.

Photographs of the hotel room which have since emerged reveal some of the weapons inside.

He was holed up in the suite with 23 guns including some modified semi-automatic rifles which had been placed on tripods and aimed at the crowds.

At his Mesquite home, police found another 19 guns and explosives.

Danley was initially feared to have been a person as interest.

It was initially feared that she may have been with her partner when the shooting occurred but police have since determined that she was in the Philippines.

She will be questioned upon her return to the United States.

58 people were slaughtered and 527 were injured in the massacre in Las Vegas on Sunday night

Concert goers were listening to country music performances when the shots began. They were then forced to run for their lives. Some heroic music fans saved others in the process and carried anyone who couldn't walk to safety

Images of the Mandalay Bay Resort show two windows blown out on the 32nd floor of the building (above) that Paddock smashed out so he could shoot crowds from two locations

It is not known how long the pair have been a couple. Danley moved to the US from Australia more than 20 years ago following the death of her husband.

She worked in the gambling industry. Paddock was an avid gambler who blew $10,000 a day on video poker.

No motive has yet been established for the attack.

Police are likely to probe his gambling debt and addiction as they try to identify what drove him to commit the atrocity.

But so far they are at a loss.

'We cannot even rule out mental illness or some form of brain damage, although there´s no evidence of that, either,' one official told Reuters on Tuesday.

The man's brother said his girlfriend was the 'closest one' to him and she would be the person most likely to shed light on his mindset.

'Mary Lou is absolutely the closest person to Steve. We are going to let her contact us if and when she decides she wants to,' Eric Paddock said on Tuesday.

Paddock was also the son of Benjamin Hoskins Paddock, a serial bank robber who ended up on the FBI Most Wanted list back in 1969 when he escaped from federal prison in Texas while serving a 20 years sentence.

The FBI kept him on the list for the next eight years, and he was eventually found one year after he was removed from the list in 1978 while outside an Oregon Bingo hall.

On Monday, Paddock's brother Eric spoke outside his Orlando home to say he had no inclination as to what drove him to commit the killings

Jordan Knights, Danley's Australian nephew, met gunman Stephen Paddock a few months ago and found him 'unremarkable'

The agency said that the fugitive had been 'diagnosed as psychopathic' and also had possible 'suicidal tendencies.'

In total, Paddock had lived in an astonishing 27 residences in Nevada, Florida and Texas over the course of his adult life.

He was once worked for the IRS and was at one point a mailman. His incredulous family are struggling to come to terms with his act of terror which they say is entirely out of character.

He was once married but divorced his wife 27 years ago. She was too stunned to speak about the attack on Monday from her home in Cerritos, California.

A sheriff who was stationed outside confirmed that she was married to the gunman decades ago for six years. They did not have any children.