THE Census and Australian Bureau of Statistics websites were shut down overnight after a cyber attack and Australians have reacted with fury.

Foreign hackers made four targeted attacks overnight causing the site to crash, the Australian Bureau of Statistics has revealed.

“It was an attack,” chief statistician David Kalisch told ABC radio on Wednesday.

“It was quite clear it was malicious.”

The system outage was not fixed overnight.

The ABS was expected to give an update on when the online census will be back up and running at 9am.

However the ABS has yet to make any annoucement surrouding the debacle and all media inquiries are now being referred to the minister.

Mr Kalisch and the minister in charge of the Census, Michael McCormack, are due to hold a press conference in Canberra later this morning.

The bureau has assured the two million Australians who managed to complete the Census before the site was shut down that their data was “secure at the ABS”.

“ABS would remind Australians that they have plenty of time to complete the Census, to well into September, and again note that fines will not be imposed for completing the Census after Census night,” ABS statistician David Kalisch said.

While it’s not the first time the online option has been available, the government widely promoted 2016 as the first year more than 65 per cent of people were expected to fill out the form online.

Australians took to social media to slam the organisation responsible for collecting and safely securing private data, with many noting the irony of being unable to log on to the secure form.

Some called it a “farce” and many worried whether they would be fined for not completing their form on time.

The outage comes after ABS Census boss Chris Libreri said the system performed well in testing and would not be a repeat of the disastrous Click Frenzy sale of 2012.

“We have load tested it at 150 per cent of the number of people we think are going to be on it on Tuesday for eight hours straight and it didn’t look like flinching,” he said earlier in the week.

“We wouldn’t do it unless we were able to safely do it, we have evolved it and we are confident.”

The ABS & Census websites are currently experiencing an outage. We're working to restore the service. We will keep you updated. Thank you. — Census Australia (@ABSCensus) August 9, 2016

ABS & Census website are unavailable. The service won't be restored tonight. We will update you in AM. We apologise for the inconvenience. — Census Australia (@ABSCensus) August 9, 2016

There will be no fines for completing the Census after Aug 9. There’s still plenty of time to complete the Census. Thanks for your patience. — Census Australia (@ABSCensus) August 9, 2016

‘GROSSLY MISMANAGED’

Benita Williams told news.com.au she was unable to connect and blasted the ABS for having “the audacity to suggest that people will be fined for not completing it.”

“They are simply delusional to believe that this was going to work and that it is reasonable to fine people for not being able to access their own website,” she said.

Richard Scherlowski said “everyone is panicking right now” and said “thank God it's only every five years.”

“They had five years to get their systems up to scratch! And we’re going to give them four years to lose our privacy ... I don’t think so.”

Kushar Perera said he had been trying for 15 minutes to log on without any luck.

“Do we get penalised if we can’t fill out today? Its not my fault!” he said. Others lashed out at the organisation for asking for information while denying access to the server as complaints flooded in from all areas of the country.

David Duddell said he spent 30 minutes trying to fill out the form with elderly parents.

“We tried multiple times and then finally tried to save the form. Again this failed. After another couple of attempts the website became completely unreachable. Very frustrated that I now have to re-complete the form,” he said.

“This has been grossly mismanaged by the government. In my opinion it was very foreseeable the volume of traffic that would be hitting the census web servers.”

Yep. Definitely technically competent enough to keep our most private data safe. #census2016 #CensusFail pic.twitter.com/w6hfRnJIXV — Joff (@joffotron) August 9, 2016

When someone who can't configure a web server tells you the same web server is very secure, be afraid. BE VERY AFRAID! #CensusFail — THE Russell (@THE_Russell) August 9, 2016

20 attempts to hit the Complete My Census button and all achieved this ... #censusfail pic.twitter.com/hY0xauvv9g — Ant Phillips (@antp01) August 9, 2016

Getting this message on ALL my devices tonight. Don't think I'm the only one somehow. :/ #CensusFail #census2016 pic.twitter.com/GAqZ9i2AHh — Nightflower Noir (@Nightflower_N) August 9, 2016

Census site down. Automated phone line unable to process call. Recorded message should just be "la la la la la I can't hear you" #censusfail — Cal Wilson (@calbo) August 9, 2016

Anyone Thot everyone logging into census will crash the system? Brilliant idea???? High call volume msg said to call later!???? — Shamala (@shamala_ng) August 9, 2016

Earlier on Tuesday the ABS said the system was “operating smoothly and as expected”.

Those having problems were urged to visit the Troubleshooting page of the Census website. This includes advice on what will happen if pages are left inactive and instructions on how to fill out all sections of the form.

It warns the secure system will close after 30 minutes of inactivity or if the internet connection is disrupted. If this occurs users will need to log back in to complete it and their information should have been saved at various points.

NO FINES FOR LATE COMPLETION

Many of those who experienced problems worried they would be fined for failing to complete the form on time.

The ABS has confirmed late completion will not lead to a fine, backing up comments made by Mr Liberi earlier this week.

The Census General manager said those who fail to complete the form will receive a knock on the door within weeks. Only if they refuse to complete it will the case proceed to prosecution.

“No one has ever been fined for being late with their Census form, the fines are only if you eyes-open refuse to a Census collector,” Mr Liberi earlier told news.com.au.

At the last Census less than 100 fines were issued and only to those who refused to fill out the form.

Australian Chris Hewitt fumed he wasted 30 minutes filling out the form that eventually failed to submit.

“The ABS saved $100 million in paper forms but wasted millions of hours of people’s time,” he said.

Michelle Ruchin said she “cannot believe ABS have the audacity to threaten fines when they cannot provide the services required. Utterly ridiculous.”

Despite problems for some, others said they managed to fill it in easily online. It's estimated around 1.3 million were successfully completed before the outage.

Well, that was easy. Census done online in 15 minutes. Now to the 7pm @abcnews. — Michael Rowland (@mjrowland68) August 9, 2016

Anyway, did the census. Took about 10 minutes — Greg Jericho (@GrogsGamut) August 9, 2016

The Census has been the subject of controversy this year with some pledging to leave their names off the form following the decision to keep data for four years rather than 18 months.

Independent senators Nick Xenophon and Jacqui Lambie, and Greens senators Scott Ludlam and Sarah Hanson-Young, will risk a $180-a-day fine by withholding their names and addresses.

Former NSW deputy privacy commissioner Anna Johnston is refusing to fill in the census at all.

That's despite the Census boss Duncan Young promising that information will remain top secret.

“Hand on heart, the security set-up in order for people to submit their information — it’s encrypted all the way through from their browsers into the ABS’s internal environment,” he said.

“Then we go through the process of separation. The information is isolated so people who can access names can’t access the rest.”

— With Wires.