Cash told Senate Estimates on Wednesday evening she had been advised that "without my knowledge" a single staff member in her office found out from a "media source" about the raid, and then told journalists.

The minister said she was not aware of the information until the raids took place. The staffer is "very distressed", Cash said, and has now resigned.

The late admission was in contradiction to earlier statements from Cash, who had denied throughout the day that anyone in her office leaked the information. She later said she was not informed about it at the time.

The AWU Sydney and Melbourne offices were raided on Tuesday afternoon in relation to donations made by the union over a decade ago when it was led by current Labor leader Bill Shorten.



AWU secretary Daniel Walton told Sky News the media arrived outside both AWU offices 15 minutes before the AWU received a phone call advising it that a warrant had been issued. Walton said that when asked, members of the media told AWU staff they were there to cover the raid.