Staff of former communications minister Stephen Conroy were told to meet the officers at a security entrance at the building this morning.

They were taken to the basement – a large maze of corridors under the building which is off limits to the general public. They were then led away to another location.

The AFP said it had obtained a search warrant and was conducting the raid with the consent of the Department of Parliamentary Services.

Police accept there has been a claim of parliamentary privilege.

“All material seized during this warrant will be handled in accordance with the provisions and guidelines relating to parliamentary privilege,” it said in a statement.

The Parliament House development follows a late-night raid on the office of Senator Conroy and a staff member during the recent federal election campaign.

Senator Conroy claimed the AFP was simply acting on the request of NBN Co, “with Malcolm Turnbull’s mates on the board who are desperate to provide cover for him”.

“The whole investigation is about covering up Malcolm Turnbull’s incompetent administration of the NBN and its rollout and its cost,” he said ahead of the latest raid.

Senator Conroy also questioned the legal justification for the company’s action in asking the AFP to investigate, given it was not a public authority.

Turnbull hit back at Senator Conroy’s attack on the integrity of police, saying the Labor frontbencher “operates in a parallel universe”.

“He knows absolutely, as well as we do, that the AFP are thoroughly independent of the government, there is no political direction at all,” the Prime Minister told reporters in Sydney as the raid was taking place.

“The administration of justice takes its course and it’s not for politicians to try to meddle in it or bully the police or any other security service into one action or another.”

Senator Conroy’s claim of parliamentary privilege will be tested when federal parliament resumes next week.

“What is at stake here is the ability of members of parliament to protect the whistleblowers who come to them and give them information that demonstrates that the government of the day is not actually achieving what it is claiming in public,” he said.

Communications Minister Mitch Fifield denied it was an investigation into whistleblowers.

“This is a case where NBN is alleging that there is theft of material which is of commercial-in-confidence and I think any organisation is within its rights to call in the appropriate authorities,” he said.

Shadow attorney-general Mark Dreyfus said he was concerned by reports the media was prevented from filming the raid.

“This is not a police state, it is a democracy,” he told reporters in Melbourne.

“There is no reason for these activities to be hidden away or done in secret. Full transparency is necessary.”

-AAP