"Be careful where you leave your cars, what Americans that have not been dragged into the war are thiefs," he wrote.
In an email obtained by the Herald on Sunday, Powell's personal assistant wrote: "Otis [Powell] text me last night to let everyone know to pack small!! I am a girl, so it is almost impossible to pack small for me, and I have a suitcase full of Hell condoms for Otis."
Powell calls the City of Sin "The Happiest Place on Earth" - and even named his son Vegas.
On another trip, Powell poses in a cowboy hat with his partner Oksana.
Yesterday he said the Las Vegas staff trip was paid for from the $15.6 million he and fellow directors Callum Davies and Stu McMullin made from the sale.
He emailed a Flight Centre travel agent to say he needed invoices for "around 30K" for tax purposes.
Powell said he could not remember if it was paid out of the marketing fund - a trust controlled by Hell directors and used to pay for advertising.
"Our marketing fund was in credit and the company had been sold. This was our money."
ON THURSDAY, Serious Fraud Office investigators swooped on commercial and residential properties in Auckland and Wellington connected to Hell Pizza.
At least six locations, including the pizza chain's Wellington head office and Powell's $900,000 Mission Bay townhouse, were searched.
Computers, cellphones and documents relating to several trusts linked to Powell and one of his companies, Abraham Black Limited, were seized.
Powell says the company has done nothing wrong and expresses confidence that neither he nor fellow directors Davies and McMullin are the targets of the investigation.
In a tongue-in-cheek move, Hell yesterday emailed hundreds of thousands of customers offering a "Squeaky Clean Sunday" $13 pizza special to customers who quoted the code "SFO 666".
It is typical of an irreverent, sometimes provocative, marketing strategy that has made Hell one of New Zealand's most well-known and controversial brands.
The SFO will go over thousands of documents relating to the company's parent companies, Hell Revolutions and Hell Franchise Limited.
Its investigators are understood to be looking at transfers from Hell Pizza's marketing fund.
The fraud office last week received allegations of financial irregularities, which Hell will strenuously deny.
Powell said the company had just come through a full audit from the Inland Revenue Department.
"We are squeaky clean. There is no mischief in our business," he said. "I am assuming that we are not under investigation."
Hell Pizza's 64 franchises pay 5 per cent of their turnover, more than $1 million annually, into the fund used to pay for the controversial advertising campaigns.
Powell said the directors "fight like bejesus" to make sure they get good value for money from the marketing fund for their franchisees.
Invoices obtained by the Herald on Sunday show transactions between Abraham Black Limited and Hell Pizza are expected to make up part of the investigation.
Powell blamed a "rogue" former employee of the company for the allegations. "We fired [him] because he was an absolute ratbag."
The former employee's home was also raided by investigators.
SFO chief executive Adam Feeley said it was too early to say whether any fraud had taken place. "We are very careful not to point fingers at any individuals," he said.
"Our first priority is looking at the evidence and whether it supports that story."
Powell said it would be business as usual for Hell while the investigation was going on.
Meanwhile, business associates of Hell have rallied in support. Marc Spring, managing director of Trinity Media Group which has done advertising work for Hell, said: "I 100 per cent believe and trust that Warren has done absolutely nothing wrong.
"He is an innocent victim. Warren is only guilty of trying to help out a friend."
