And for about six months, the two young men – Facebook friends, aged 26 and 24 – appeared to have avoided suspicion.

But for a scheme where manipulation of timing was everything, it was time records which came to catch them out, according to documents presented in court on Saturday.

The court documents state the plan between sacked NAB worker Lukas Kamay and suspended Bureau of Statistics employee Christopher Hill was doomed after a tip-off to the Australian Securities and Investment Commission by an online broker in February.

Foreign exchange derivative trades by Mr Kamay minutes before the official 11.30am release of ABS data had led to windfall profits.

It is alleged the source of the lucrative information was Mr Hill, with the two men appearing to have got back in touch for the scam, evidence suggests.

Call records showed phone contact was first observed between the pair on August 7 last year. On August 9, Mr Kamay set up of the first of four trading accounts allegedly used in the scam.

The AFP tracked the two men, recording their movements during a meeting in Melbourne in late April where two phones were purchased under false names.

According to a tapped conversation, Mr Kamay promised to give Mr Hill $60,000.

They agreed to mimic legitimate trading patterns by deliberately incurring losses as well as profits in order to avoid suspicion. On May 2 this year, Hill called Mr Kamay, allegedly telling him “yeah I got a bit for you, all three”, with Mr Kamay replying “let’s go”.

Mr Hill is understood to have been referring to confidential retail trade, building approvals and labour force statistics he had obtained through his work at the ABS.

Details were allegedly retained on a piece of paper before being called through.

The documents show 23 trades were conducted between September 2013 and May this year through the four accounts, with the biggest single-day profit, more than $2.5 million on March 13.

Mr Kamay would enter positions on the foreign exchange markets shortly before 11:30am on the official release date of the data, and exit the positions shortly thereafter.

During the raid on Mr Hill’s Belconnen home on Friday he denied knowledge of the phone bought under a different name and refused to talk to police during a subsequent interview. Mr Kamay was also arrested on Friday after search warrants were executed at seven premises across Melbourne and Canberra.

Mr Hill is charged with offences including conspiracy to commit insider trading, accepting a bribe as a Commonwealth public official and dealing in the proceeds of crime.

On Saturday an ACT magistrate refused to grant Mr Hill bail, and federal police escorted him on a flight to Melbourne, where his family reside, ahead of a court appearance on Monday.

Prosecutor Sara Cronan described an “extraordinarily strong” case against Mr Hill, and said a prison sentence for him seemed “pretty inevitable”.

Mr Kamay was bailed in Melbourne on Friday, on the condition he reside at his family’s suburban home.