Scott Morrison's office says it has found no correspondence from Daryl Maguire

Scott Morrison’s office says preliminary searches have not located any correspondence from the disgraced New South Wales MP Daryl Maguire during Morrison’s time in the immigration portfolio, or while he has been prime minister.

During a hearing last week in the NSW independent commission against corruption, Maguire admitted to receiving thousands of dollars in cash to his parliamentary office from a former business associate, Maggie Wang, in relation to a “cash-for-visa” scheme the two established.

With controversy persisting on Tuesday about the role of commonwealth officials in a controversial land sale at Leppington Triangle related to the second Sydney airport, Morrison was also asked by Labor during question time whether Maguire had made any representations to the government about visas.

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Immigration ministers are flooded routinely with appeals from stakeholders and members of the public, and Morrison left open the possibility of contact with Maguire in his parliamentary answer.

The prime minister’s office later issued a non-definitive statement saying the home affairs department had advised that “a first, complete search of its database did not identify any correspondence from Daryl Maguire or the business G8wayinternational Pty Ltd … in his former role as immigration minister”.

The statement said additional searches carried out by the office indicated the prime minister had “not received any such correspondence in his current role”.

Morrison told parliament on Tuesday police should investigate all of the issues associated with the government’s controversial Leppington Triangle land purchase – a transaction that has been excoriated by the Australian National Audit Office – “absolutely thoroughly”.

The Australian federal police has indicated it will contact the NSW Icac and review more than 800 files supplied by the audit office, as part of its criminal investigation into the purchase of a block valued at $3m for $30m.

Explaining the planned outreach to Icac at a Senate estimates hearing on Tuesday, the AFP’s deputy commissioner, Ian McCartney, said the AFP would seek to satisfy itself that Maguire did not have any role in the purchase.

“That would be our primary focus of engaging Icac at the minute,” McCartney said.

The AFP is not the only federal agency engaging with Icac: the Department of Home Affairs is also in contact with the corruption watchdog over the visa matters.

The head of Home Affairs, Michael Pezzullo, said on Monday he had ordered a review of records related to the visa matters, and he believed Maguire had made representations to federal MPs or Home Affairs.

Labor targeted Morrison and his ministers over the land sale issue in question time on Tuesday. The deputy prime minister, Michael McCormack, was asked to explain his observation that the purchase in time would be seen as a “bargain”.

McCormack on Tuesday acknowledged the infrastructure department had paid “way over the odds” for the parcel of land for future growth of the western Sydney airport, but he came close to repeating his previous claim that time would render the purchase more favourably.

“In time, people will look back at this moment and say, ‘thankfully the commonwealth instigated that in 2020’,” McCormack said.

Paul Fletcher, who previously served as cities and urban infrastructure minister, told parliament he stood by his answers to questions at the National Press Club month.

Fletcher had argued last month the briefing material provided to the deputy secretary and himself over the land purchase was “deficient”, because it failed to disclose “key pieces of information” that would have allowed them to assess whether what was paid was reasonable.

The AFP disclosed on Tuesday that the ANAO had provided the AFP with 256GB of information and police were now working their way through the material. The investigation began in July but only publicly disclosed last week.

When the Labor senator Kristina Keneally asked whether the investigation would look at possible breaches of divisions 134 and 135 of the Criminal Code, which criminalises obtaining property by deception or other fraudulent conduct, McCartney, said: “Correct.”

McCartney said the AFP was also focusing on division 142 of the Criminal Code, “which is corruption of public officials – it’s an offence that we’ll assess”.

Icac has been exploring a different, proposed major land sale worth $330m involving racing heir Louise Raedler Waterhouse and a large plot near the proposed Western Sydney airport, known as SmartWest – but this is not currently part of the AFP investigation.

Three federal infrastructure department officials and federal MP Angus Taylor separately met with Waterhouse in 2017 while she lobbied for changes to her vast landholdings near the airport, according to public documents.

Reece Kershaw, the AFP commissioner, confirmed he was first approached by the auditor general, Grant Hehir, about the Leppington Triangle land purchase by telephone on 10 July. They discussed “what the auditor general had discovered” and “what the process of a [formal] referral would look like”.

The auditor general’s report found the price of land to build a second runway after 2050 was inflated by $26.7m above its fair value by a decision to include the land’s “speculative industrial rezoning potential”.

On Monday evening, Hehir told Senate estimates he had contacted the AFP because he “couldn’t explain” the infrastructure department’s approach to the purchase and the material was “suggestive that the commonwealth may have been defrauded”.

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Kershaw confirmed he then received a letter from Hehir around the 13 July, with attachments outlining the valuation approach, the comparison of the price paid against nine valuations, and some other material.

McCartney said the AFP had made a decision on 27 July to initiate an investigation, focused on the discrepancy between the sale price and the valuations.

He said he would still describe the investigation as being at an early stage, and the AFP was yet to identify any criminality.

Pressed on whether the AFP could rule out a focus on officials, ministers or ministerial advisers, McCartney said: “We can’t rule anybody out but we can’t rule anybody in either.”

The AFP said it had informed the office of the home affairs minister, Peter Dutton, on 22 September, when the ANAO report was released, that a police investigation was underway. But it did not inform the current infrastructure minister, McCormack, or his office.

When the infrastructure department contacted the AFP on 8 October about the possibility of referring the matter to the police, the department was informed that police already had an active investigation based on the ANAO’s referral.

Officials from Morrison’s department were rebuked by Labor during a separate estimates hearing for mixing up the date they learned the Leppington controversy had been referred to the AFP.