INSIDE the lavish, sprawling estate at the end of a quiet cul-de-sac in Narre Warren, southeast of Melbourne, Ngouth Oth Mai and his family lived the good life.

The $1.5 million mansion, fully paid up, featured an infinity pool, a sauna, a cinema, a five-car garage, a pool table, massive bedrooms and sparkling bathrooms.

But how did a 22-year-old from housing commission flats on a humanitarian visa and Centrelink handouts pay for it all?

That’s the question at the centre of an Australian Federal Police investigation that Oth Mai will be asked to answer in court in July.

The AFP are not the only ones asking. The George Clooney-spearheaded anti-corruption watchdog The Sentry is demanding answers, too.

Police were tipped off to the unusual acquisition of the property at Wiringa Close when The Sentry began sniffing around in 2016. The property was seized and a massive investigation that followed has now been revealed in court documents seen by news.com.au.

An affidavit filed by the AFP as part of civil action in the County Court of Victoria claims the property was paid for with proceeds of crimes linked to Oth Mai’s father, former Sudanese General James Hoth Mai.

James Hoth Mai is the one-time chief of staff to Sudan’s People’s Liberation Army.

“In September 2016, following the receipt of information that several former and current South Sudanese officials maintain properties in Australia that may have been purchased with the proceeds of corruption, the AFP commenced an investigation, code named SIBUDU,” the affidavit said.

It names James Hoth Mai, his son Ngouth, his wife Nyawarga and his daughters Titchiang and Dijok. James does not live in Australia, but the others moved from Sudan to Melbourne on humanitarian visas in 2001 and 2003.

Since then, they have allegedly lived in commission housing, received hundreds of thousands of dollars from Centrelink and reported no income to the Australian Taxation Office.

The AFP’s affidavit claims records show Ngouth, his mother and his sister received a combined total of more than $460,000 from Centrelink.

The AFP alleges Ngouth purchased the Narre Warren property after setting up a fake business in 2014 ostensibly to import luxury cars to Australia. Ngouth had an 80 per cent shareholding but the company did not make any money or conduct any actual business.

The car import business was named Sportscars Pty Ltd. Ngouth set up two accounts for the business with the National Australia Bank and the AFP claims money started rolling in. Sums of $621,838, $470,756, $312,838, $82,897 and $58,978 were wired into the NAB accounts from Uganda and Kenya, through banks in Dubai.

On June 5, a sum of $155,171.77 was wired from the Sportscars account to a Trust account for real estate agents Harcourts Berwick.

On August 21, 2014, Ngouth allegedly transferred $1,405,195.66 from Sportscars’ Business Cash Maximiser account into a second account and withdrew a sum of $1,360,661 to make a cheque payment towards settlement of the property.

The AFP claims the property was paid for by the 22-year-old despite him having no credible source of income.

“At the time of the purchase ... he was not employed and had been receiving youth allowance from the Australian Government since 2008,” the AFP’s Graham White said in the court documents.

“Ngouth used the funds in Sportscars NAB bank account to purchase the Narre Warren property in his sole name ... I suspect that Sportscar was set up for the sole purpose of moving money from overseas into Australia to purchase the property without alerting Centrelink.”

The family home is not the only purchase under scrutiny. Titchiang is the registered owner of a 2016 Audi A1 purchased for $35,274 on August 17, 2015 and Dijok is the registered owner of a BMW 316i, purchased a week later for $63,000.

Police say the Audi was purchased with money wired through the Sportscars account and $8000 cash.

“My investigations show that the bank accounts of Ngouth, Nyawarga or Mai do not reflect any corresponding withdrawals that can account for the origin of the (Audi money) deposit into Sportscars’ bank account,” Mr White said.

The Sentry’s investigations director J.R. Mailey told the Herald Sun earlier this year that Ngouth’s purchase of the Melbourne home was “noteworthy and worthy of additional scrutiny for several reasons”, including that military generals in the African nation like James Hoth Mai typically earn less than $70,000 a year.

“First, the cost of the home far surpassed what one could reasonably afford on the salary of a general of Hoth Mai’s rank,” he said.

“Second, the Hoth Mai family had purchased the home shortly after having resided in subsidised housing, a major sudden change in the family’s lifestyle.

“Finally, the home was purchased in the name of Hoth Mai’s son, who had only recently graduated from college.”

News.com.au has reached out to Ngouth Oth Mai’s lawyers for comment. Earlier this week, solicitor Leath Nicholson told the ABC his client is a person of impeccable character and the AFP claims are without merit.

The case will be heard in July in Melbourne.

rohan.smith1@news.com.au | @ro_smith