According to the ABC, Anglo’s legal team believes 50-year-old Tonkin received the money through fake invoice-related schemes and contract winning kickbacks, with the funds siphoned off to private bank accounts in London and Barbados.

He reportedly quit his job last month, which included overseeing Anglo’s flagship $2 billion Grosvenor longwall project in Queensland and signing off on contracts of up to $15 million, after Anglo’s human resources head confronted Tonkin with evidence of email tampering following a tipoff from a co-worker.

“The former executive has claimed privilege over a laptop alleged by Anglo to be missing, and a range of documents sought by Anglo's lawyers relating to bank accounts, saying that to reveal them could incriminate him in criminal proceedings,” ABC reported.

Almost $3 million of the allegedly ill-gotten gains came in the form of payments from three Anglo contractors to New York registered and London-based Advanced Mining Services for “consulting services that were never provided”.

“Investigators working for Anglo found the London address for AMS was a mail-forwarding service,” ABC reported.

“The woman running the office told the investigators the company's owner was ‘an Australian gentleman’ who did not visit London very often.”

Separately Tonkin is reportedly facing claims he misappropriated hundreds of thousands of dollars through a fake invoice scheme involving Florida-based Motor Protection Electronics.

“A series of emails filed as exhibits to the documents appear to show Mr Tonkin discussing MPE invoices with a person called Hank Testolin, MPE's sales manager,” ABC reported.

“But when Anglo's head of human resources contacted MPE in Florida, the US company told him it had never employed anyone with that name, it was not doing any business with Anglo and was not shipping any goods to Australia.”

Brisbane’s Supreme Court has reportedly issued orders to freeze $1.5 million of Tonkin’s assets after he revealed owning $3 million worth of property, a $7000 catamaran plus several cars and motor bikes.

All the parties involved have refused to comment on matters before the court.

Anglo was previously paying Tonkin a salary of more than $350,000 a year.

Anglo’s head of underground operations, Glen Britton, known for ushering in stellar results at Anglo’s Moranbah North longwall mine, has become the executive in charge of the Grosvenor project since Tonkin quit.

Targeting a mine life of 30 years, the under-construction Grosvenor mine is expected to produce 4.3 million tonnes per annum of metallurgical coal with full production targeted for 2016.

Run-of-mine production is expected to reach up to 7Mtpa, with this output to be transported via an overland conveyor for processing at Moranbah North.