Sydney construction identity George Alex will remain behind bars over the weekend on charges of leading a criminal syndicate staging an elaborate $17 million tax fraud scheme.
NSW, Queensland and ACT properties were raided on Tuesday after an 18-month joint investigation into tax fraud and money laundering by Australian Federal Police, the Australian Tax Office and corporate regulator ASIC.
Police have charged 12 people in connection with the crime group including seven men in Queensland, two men and two women in NSW and an ACT man.
Alex, 49, and his 22-year-old son Arthur were among those arrested on the Gold Coast.
He was this week extradited to NSW and faced Sydney's Downing Centre Local Court on Friday on charges of conspiring to cause loss and dealing with proceeds of crime exceeding $1 million.
The matter was held over to Monday for a hearing at the same court, with a bail application flagged by Alex's legal representatives.
He did not apply for bail on Friday and it was formally refused by magistrate Robert Williams.
It is alleged the Alex-led syndicate used labour-hire and payroll companies to withhold and launder more than $17 million in owed taxes though elaborate "phoenix" activity.
This process involves the creation of a new company to replace a deliberately liquidated debt-ridden business to avoid paying tax, creditors and employee entitlements.
Federal police say they have seized $21 million worth of assets connected to the syndicate including 12 properties, 17 vehicles, 65 bank accounts, a caravan and a boat.
Another $1.3 million in Singapore bank accounts has been frozen.
"They will deal in anything that makes them money and they're actively recruiting specialists from the finance, accounting, legal and banking sectors," AFP investigations commander Kirsty Schofield told reporters on Wednesday.
"This syndicate specifically included a mix of financial industry experts to provide the level of expertise required to commit the fraud and keep it ongoing."