The Communications Minister, Stephen Conroy, has accused Google of launching "the single greatest breach in the history of privacy".

The spray, during a Senate estimates hearing, is just the latest in a series of attacks by Senator Conroy on the search giant following Google's criticism of the government's forthcoming internet censorship regime.

The minister's critics have rounded on him this morning, calling last night's comments just another "petulant" and "hysterical" attempt to bad mouth people and companies critical of his policies.

Likes his sport ... Stephen Conroy.

"On a hair trigger" ... Communications Minister Stephen Conroy.

Senator Conroy's comments refer to the recent privacy furore sparked by revelations that Google accidentally gathered 600GB worth of private data from open Wi-Fi networks while taking pictures for its Street View mapping service around the world.

The move has landed it in hot water from several privacy regulators, who have accused the company of unlawful interception of users' data, including audio, video, documents and emails. It could then potentially link these intercepted documents to a specific address.

Google has argued that the data was collected by mistake but Senator Conroy rejected this, saying it was "actually quite deliberate" and Google "wrote a piece of code designed to do it".

"I think that the approach taken by [Google CEO Eric] Schmidt is a bit creepy, frankly," Senator Conroy was quoted by ABC News Online as saying.

"They [Google] consider that they are the appropriate people to make the decisions about people's privacy data and that they are perfectly entitled to drive the streets and collect as much private information by photographing over fences and collecting data information.

"This is probably the single greatest breach in the history of privacy."

The full hansard transcript of Senator Conroy's spray will not be published until late today or tomorrow.

In a phone interview this morning, Greens communications spokesman Scott Ludlam confirmed that Senator Conroy labelled the Google Wi-Fi debacle the single greatest breach in the history of privacy.

This seems to be at odds with the thoughts of the Australian Privacy Commissioner, Karen Curtis, who has launched an investigation into the matter but has previously played down the seriousness of the privacy threat.

Today, Curtis, who met Google last week, said she was still investigating the company's collection of Wi-Fi payload data and was awaiting a response from Google to further questions. She refused to provide any further comment.

"The minister's on a bit of a hair trigger so anyone who's criticised the net filters becomes a target for character assasination, whether it be an advocacy group like EFA [Electronic Frontiers Australia] or one of the world's largest technology companies like Google," Senator Ludlam said.

"It comes across as really petulant - the guy's a minister of the Crown, you don't need to be bawling out technology companies just because they've taken a critical stand on his filter."

"I just think the minister's being a little bit oversensitive to criticism - it would be helpful sometimes if rather than shooting the messenger he listens to what he's being told."

Senator Ludlam and Colin Jacobs, chair of Electronic Frontiers Australia, both agreed that the Google Wi-Fi bungle was a serious matter but said Senator Conroy appeared to be beating it up for political gain.

"The Minister's hyberbole, bordering on hysterical, is counter-productive," said Jacobs.

"We need a measured assessment of the risks and issues, not a personal vendetta against a company that has publicly disagreed with the Minister on his censorship policies."

In the same estimates hearing, Senator Conroy also sounded off against Facebook over its recent privacy failings, accusing it of having a "complete disregard for users' privacy lately".

Google issued a terse response to Senator Conroy's spray, saying: "We were surprised to hear more discussion about Google and Facebook than about the actual proposed filter."