Former Communications Minister Stephen Conroy is seeking NBN chairman Ziggy Switkowski’s resignation in the wake of raids on Labor offices during the election campaign.

Acting on a referral from NBN Co, Conroy’s offices and other Labor premises were searched by the Australian Federal Police (AFP) in relation to a series of damaging leaks on the National Broadband Network project.

A number of documents were seized in the searches but they have been sealed while a ruling is sought on whether they are covered by parliamentary privilege.

Speaking on ABC Radio National this week, Conroy revealed he had written to the AFP repeatedly in the six weeks since the raids, seeking assurances on electronic communications that may have been intercepted as part of the investigation, and most recently questioning the legality of the raids.

“I’ve written to the Federal Police on Friday [July 1] asking them to end their ludicrous investigation into leaks on the NBN on the basis of legal advice that says NBN Co have incorrectly called the police in,” Conroy said.

“They are not Commonwealth officers, and I am seeking and demanding an end to the investigation, an apology from Ziggy Switkowski, an apology from [Communications Minister] Mitch Fifield who’s overseen this, and Ziggy Switkowski resign over it.”

Fifield, who was with Conroy on the same program, replied that he “won’t be apologising to Stephen”.

“I didn’t raid Stephen’s office. The Australian Federal Police did,” Fifield said.

“The referral from the NBN to the AFP was a matter for NBN, and the AFP determine what is and is not in their jurisdiction.

“It’s entirely a matter for the Australian Federal Police. They have operational independence and to question the AFP and their motives is to question the integrity of that organisation”.

Fifield became embroiled in the issue after it was revealed he was aware of NBN’s referral to the police, but did not inform others in his party about it.

NBN has defended its right to call in the police over the leaks after it was unable to trace the source during its own internal investigation.

However, the organisation courted controversy when Switkowski ignored advice and defied caretaker conventions during the election campaign to publicly defend the pursual of the leakers.

NBN said it had “followed and complied with instructions from the AFP at all times.”

Two NBN staff were stood down over the leaks.