Investigators have partly blamed being time-poor and under-resourced for not pursuing a probe into a transport department official who allegedly turned out to be the mastermind behind a multimillion-dollar kickback scheme, an anti-corruption inquiry has heard.

Appearing before the inquiry into department staff pocketing kickbacks from road contractors, Transport for NSW investigations officer David Faust was questioned on Thursday about an anonymous complaint he was asked to examine in July 2023 about official Ibrahim Helmy.

Helmy is accused of being the mastermind behind corrupt relationships with nine companies that were paid at least $343 million in contracts by the government agency in return for paying bribes to him and other officials.

The inquiry by the Independent Commission

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