Las Vegas suspect was a mystery even in his own retirement town

This undated photo provided by Eric Paddock shows his brother, Las Vegas gunman Stephen Paddock. On Sunday, October 1, 2017, Courtesy of Eric Paddock / The Associated Press

In the quiet cul-de-sac where Stephen Paddock lived, even his immediate neighbours say they did not know him.

Some say they never set eyes on the man accused of spraying an outdoor concert with bursts of gunfire from high above in a Las Vegas hotel window on Sunday, killing 58 and wounding more than 500, before shooting himself.

Tracing Paddock's footsteps in Mesquite, the Nevada desert retirement community about 145 kilometres northeast of Las Vegas, provides scant clues about why, according to authorities, he carried out the worst mass shooting in recent US history. Hardly anyone noticed the man.

"Nobody knew him. I literally never saw him," said a neighbour who lives two doors down from Paddock's home and who declined to be named. "The house was so quiet, we thought they were snowbirds," he added, referring to retirees who spent the winter months in warm-weather places like Mesquite.

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Garbage cans were put out on the street before anyone else was even awake, leaving no opportunity for casual chats with neighbours living just feet away. Yard work was done by gardeners. Pizza came directly to the door, and as far as anyone knew, Paddock never took part in bingo or bocce, or any of the social activities provided by the retirement community.

By all accounts, Paddock was a man of few words who never sought to interact with others beyond his live-in companion, Marilou Danley, a 62-year-old former casino employee described by authorities as person of interest in the investigation.

Neighbours immediately next to Paddock's mustard-coloured stucco home, landscaped with stones and desert plants, displayed a sign on their door: "We did not know him."

The mangled remains of Paddock's garage door sat in his driveway, after authorities searched the home on Monday, uncovering a cache of 19 firearms, explosives and thousands of rounds of ammunition.

Paddock, who worked as an apartment manager and aerospace industry worker over the years, was known as an avid gambler. He would venture out of his Mesquite home frequently to play poker at the local casinos, where regulars recalled his face but little more.

The 64-year-old would often stop at Starbucks, where baristas remembered him as quiet and "in his own world".

And according to one barista, Paddock appeared "rude" when he ordered a Mocha Frappucino for Ms Danley, instead of letting her order for herself.

"He didn't let her talk," the employee said.

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Paddock seemed more sociable to those who delivered him pizza from Domino's 14 times in recent months. A good tipper, Paddock paid cash and always ordered the same thing — two medium mushroom pizzas with extra cheese.

Sometimes he would tell the delivery person he was trying to lose weight and the pizza was only for his companion.

Domino's employee Jessie Givens recalled that Paddock would joke to her: "It's not fair! She gets to eat pizza — and I don't."

Ms Danley, who was in the Philippines at the time of the attack, returned to the United States late on Tuesday, arriving in Los Angeles from Manila. She could reveal more clues about Paddock's motives when investigators interview her.

Paddock was known to have previous relationships, none of them recent.

Court records show that he got married in 1977. The couple separated in 1979 before their divorce was finalised in 1980 in Los Angeles County.

Five years later, Paddock married again, separating in 1989 and divorcing in 1990, also in Los Angeles County, according to court and public records.

In both cases, divorce papers cited irreconcilable differences.