They were security alerts, warning US firearms dealer Brandon Maddox that someone was trying to access the online accounts for his e-commerce business, Federal Firearms License 123.

The attack was coming from 14,200 kilometres away, in Sydney.

Within days, a near-identical copy of Mr Maddox's website, FFL123.com, had emerged online.

FFLTrust.com was selling the same e-book on how to get a US firearms licence and sending email promotions to Mr Maddox's database of 200,000 customers.

The site claimed to have licences to buy and sell military-grade weapons in seven US states but the licence holder, Henry Smith from Texas, listed a non-existent address and Mr Maddox's company name was accidentally left in the fine print.

Mr Maddox, who owns gun stores in seven US states, found his website had disappeared off Google search results. He'd lost his 11-year-old business overnight.

"My business is like my baby. This business puts food on the table for my family," he said. "Having your entire business and personal accounts hacked creates an incomprehensible feeling of being vulnerable and violated, the feeling never goes away."

The new site is owned by Platinum Avenue Holdings, a company set up by Iranian-born 30-year-old Milad Oskouie in the basement of his parents' home in Willoughby, on Sydney's north shore. A Commonwealth Bank account in his name is attached to the business.

???In a bizarre story of international hacking and subterfuge, Fairfax Media has traced Mr Oskouie's alleged trail of online destruction and located him in London where he is running a website writing "plagiarism free" essays and theses for university students in Australia, Britain and the US.

Not long after Chatswood detectives knocked on his door last year, neighbours said Mr Oskouie disappeared. His father also left for months, citing "family troubles".

Before his departure, he would be seen almost every day and night walking up and down the quiet suburban street, always carrying an old leather briefcase and a can of Coca Cola.

One neighbour, who asked not to be identified, described his mother, a childcare worker, and father, a builder, as nice but Mr Oskouie as "always gloomy and a bit spooky".

Now living in a west London apartment, Mr Oskouie has established a British company, Osko M, to run an essay-writing business, TheUniTutor.com, that claims to have thousands of customers.

Yet Fairfax Media has found that staff profiles on the website are fake, such as UniTutor's "general manager and former London School of Economics lecturer" Frank Delaney, whose photo is actually of a Turkish engineer named Abdullah R. Gulhan.

"LSE has never employed anyone by the name of Frank Delaney," a university spokesman said.

A photo of "customer services manager" Vanessa Nixon is actually Hungarian banker Zsuzsa Bors??nyi's LinkedIn profile picture.

"The photo is mine but I am not Vanessa. It makes me really upset," Ms Bors??nyi told Fairfax Media.

Mr Maddox said the reason why Mr Oskouie allegedly targeted him is hard to believe.

He paid an India-based freelance web consultant to do a one-off job in 2013 to help optimise traffic to his site.

After the work was done, Mr Maddox provided a testimonial for the consultant, who said he was starting up a business with a Sydney lawyer, Milad Oskouie, called Infinite Conversions.

Mr Maddox was angered when a case study appeared on Infinite Conversion's website revealing his sales data. He repeatedly asked for it to be taken down, encountering hostility from Mr Oskouie. Five months later, the late-night emails began.

"My kindness erupted into a nightmare," he said.

Eighteen months on, he says he has spent $25,000 on lawyers and engaged almost a dozen law enforcement agencies across three continents and at least nine internet service providers.

In turn, Mr Oskouie has fired off counter notices for copyright infringement and threatened to have Mr Maddox charged for harassment over a letter sent to his parents.

NSW Police found that Mr Maddox's accounts were accessed from two internet cafes in Chatswood and therefore had insufficient evidence to lay charges. They referred it back to US authorities for civil action.

Last week, FFLTrust.com was taken down by its hosting company after a US court implemented a temporary restraining order due to the likelihood it would be found to constitute copyright infringement and deceptive trade.

Mr Oskouie's assets, including a US bank account with a substantial balance, have been frozen.

After Fairfax Media contacted him, he removed the fake staff profiles on TheUniTutor.com and said he had only bought the site weeks earlier.

He denied stealing any content for FFLTrust.com, saying he sells how-to guides that are easy to make.

"[Mr Maddox] is using the guise of hacking to stop any competition," he said. "He's threatened by a competitor."

He promised to show evidence incriminating Mr Maddox if Fairfax Media spoke to his Sydney lawyer, Robert Haralovic. Mr Haralovic didn't respond to requests for comment.