A SEX worker has told how Las Vegas gunman Stephen Paddock acted out violent rape fantasies and bragged: "I was born bad."
He boasted in text messages about his father Benjamin being a bank robber who escaped jail in 1969, reports The Sun.
He wrote: "I didn't have anything really to do with him but the bad streak is in my blood. I was born bad."
The escort described him as "obsessive" and "paranoid" and said he would rant about conspiracy theories, including claiming 9/11 was an inside job by the US government.
The woman, 27, saw Paddock, 64, around nine times from November 2015 to June 2016 when he would visit Las Vegas without his girlfriend Marilou Danley, 62.
Paddock - who made $5.8 million in 2015, mostly from gambling - would pay her up to $10,000 a time.
They even stayed in the Mandalay Bay, from where he was to open fire on a music festival, slaughtering 58 before killing himself.
The escort, who does not want to be named, said: "When I first met Stephen I had left an abusive relationship and was starting all over again with nothing but the clothes I was wearing.
"He seemed like he wanted to help. We would go to the casinos together and he would spend hours drinking and gambling.
"But when he would have a winning streak, we would go back and have really aggressive and violent sex."
The Sun was shown text messages which appeared to show Paddock discussing tying her up "as you scream for help".
The escort broke off contact when she started a new relationship.
"He had a dark and twisted side. But even so, I could never have imagined he would do something like this."
Police are still at a loss over a motive for Paddock's rampage a week ago.
The comments from the sex worker come days after a US official said investigators believe the Las Vegas shooter may have hired a prostitute in the days before the shooting and are interviewing call girls as they look for clues into his motive.
Officials have reportedly confirmed a woman who was seen with gunman Stephen Paddock days before the massacre was a prostitute, according to ABC News.
Another official said Friday that prostitutes are among the hundreds of leads they are pursuing as part of their investigation into Paddock.
The official, who was briefed by federal law enforcement officials, wasn't authorised to discuss the matter publicly and spoke to The Associated Press on condition of anonymity.
The official also said that Paddock had taken at least a dozen cruises out of the US in the last few years, most with his girlfriend Marilou Danley. At least one sailed to the Middle East.
So far, examinations of Paddock's politics, finances, any possible radicalisation and his social behaviour - typical investigative avenues that have helped uncover the motive in past shootings - have turned up little. "We still do not have a clear motive or reason why," Clark County Undersheriff Kevin McMahill said.
"We have looked at literally everything."
The FBI announced that billboards would go up around the city asking anyone in the US with information to phone 800-CALL-FBI.
"If you know something, say something," said Aaron Rouse, agent in charge of the Las Vegas FBI office.
"We will not stop until we have the truth."
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