A Fair Work Ombudsman (FWO) official contacted two staffers for Employment Minister Michaelia Cash on the day of the controversial police raid on the Australian Workers Union, including the ministerial advisor who resigned for tipping off the media.

The revelation confirms for the first time that the employment watchdog communicated with the Minister’s office in the hours surrounding the October 24 raid, which the AWU is challenging in court as a politically-motivated witch hunt.

Documents obtained by The New Daily reveal that FWO media director Mark Lee communicated with David De Garis, Ms Cash’s former media advisor, via text message and email on the day that investigators swooped on AWU premises.

That operation was part of a probe into the union’s compliance with political donation rules.

The new documents, released in heavily-redacted form under freedom of information laws, also reveal that Mr Lee exchanged emails with Alexandra Hordern, Ms Cash’s office administration manager, at some time on October 24.

The FWO deleted large sections of the communications, citing an ongoing AFP investigation into the media leaks, making the exact timing and most of the content of the correspondence unclear.

The only time-stamped communications to be released are an ROC press release sent by Mr Lee to Mr De Garis at 6.31pm, and a text message sent by Mr De Garis at 6.11pm asking Mr Lee to call him.

The raid on the AWU began at approximately 4.30pm.

A spokesperson for Ms Cash said the communications between Mr Lee and Ms Hordern were unrelated to the AWU and noted that the times indicated on the other correspondence were later than the time of the raid.

A FWO spokesman declined to comment, citing the risk of prejudicing the ongoing AFP investigation.

Mr De Garis resigned in October after admitting he had leaked details of the raid ahead of time, hours after his boss allegedly misled Parliament by insisting her office had not tipped off media. He did not reveal his source.

Mr Lee has carried out media advisory work for the Registered Organisations Commission, the agency leading the probe into Bill Shorten’s old union, in addition to his role with the FWO.

Prior to the raid, Mr Lee had been due to take up employment in Cash’s office. He subsequently ruled out the move following scrutiny over his connections to the Minister.

In October, Fair Work Ombudsman Natalie James told Senate estimates that no one from her office had any external communication about the raid before it was carried out.

The AWU said the communications uncovered by The New Daily bolstered its suspicions that the probe was politically tainted.

“This is yet more evidence of what we have long suspected: that supposedly independent watchdogs have been made into political attack dogs by Michaelia Cash and her office,” AWU acting national secretary Misha Zelinsky said.

Using millions of taxpayer dollars to set up fronts to go after your political enemies is the kind of thing you would expect in a tinpot dictatorship.

It is imperative we find out exactly what the ROC told Cash’s office and vice versa. The truth can’t be hidden behind convenient redactions forever.”

Earlier this month, the AWU had a major victory when the Federal Court ordered Cash and other related parties, including De Garis and Lee, to turn over documents to assist its bid to challenge the legitimacy of the raid.