The Federal Government now says a cyber attack was not to blame for the MyGov website falling over this morning as thousands of Australians tried to access Centrelink payments amid the coronavirus pandemic.

Key points: The MyGov website crashed amid unprecedented demand for welfare payments

The MyGov website crashed amid unprecedented demand for welfare payments The Government had claimed the system suffered a distributed denial of service attack

The Government had claimed the system suffered a distributed denial of service attack There were long queues outside Centrelink offices as large parts of the economy shut down to contain coronavirus

Government Services Minister Stuart Robert told Parliament there was no evidence of an attack, mere hours after he claimed a distributed denial of service (DDoS) cyber hack had occurred.

The website crashed, and there were long lines outside Centrelink offices around the country, after the Federal Government announced it was closing down large parts of the economy in a bid to contain the coronavirus pandemic.

Mr Robert had claimed MyGov buckled under pressure under the twin impacts of the increased demand and the DDoS attack.

"More than 55,000 Australians [were] trying to access [the site] at the same time, as well as the issue we had with the denial of service attack," he said this morning.

He later pulled back on that claim in Parliament, and said the flood of people trying to access the site had triggered alarms which are activated when there is an DDoS attack.

In a DDoS attack, hackers flood a website with users so that the site becomes overloaded. It's the type of attack that was used to bring down the Census website in 2016.

Demand for MyGov services has risen dramatically, with many Australians who have been stood down due to extra coronavirus restrictions seeking access to unemployment benefits.

From midday on Monday thousands of businesses, including pubs, gyms and restaurants, have been told to close their doors.

The Government's $66 billion second-stage stimulus package includes a doubling of dole payments, as it seeks to cushion the economy from the devastating impact of the pandemic.

Dozens of people queued outside the Centrelink office at York Street in South Melbourne this morning. ( ABC News: Ron Ekkel )

Queues outside some Centrelink offices stretched around the block this morning.

"There is unprecedented demand for the service right now, but Australians need to be patient. Try logging on later today or even tomorrow," Mr Robert said.

Centrelink offices have seen huge queues. ( ABC News: Julia Feder )

"MyGov is working, but the best option right now is for people to be patient."

In a statement, Centrelink confirmed it was experiencing "very high demand across all services" and urged people not to come into centres unless there was a "critical need" to be there.

Centrelink said new claims could be started online and if proof of ID was required, it could be provided over the phone if someone was in self-isolation.

However, people are being encouraged to defer their applications until later "if you can."

Gym worker Medhi Bachkat said he was trying to stay positive despite waiting for hours outside Centrelink at Surry Hills in Sydney this morning.

"I've gone from having an income to having no income in the last two weeks," he said.

People had to wait for hours outside Surry Hills Centrelink in Sydney. ( ABC News: Mark Reddie )

"We still have to pay for our rent and our lifestyle, so I don't know what's going on.

"I'm not trying to be stressed or anything, but no-one's smiling or happy. Everyone's grumpy."

Cherie Grant, 26, and Rhiannon Stella, 21, both lost their hospitality jobs last night.

They arrived at Centrelink in Victoria Park in Perth an hour and a half before it opened.

"We don't have any second form of income so this is what we have to do," Ms Grant told the ABC.

Cherie Grant and Rhiannon Stella lost their jobs in the hospitality industry. ( ABC News: Marcus Alborn )

Opposition frontbencher Bill Shorten said the unprecedented demand was "entirely foreseeable" and said Mr Robert must do better.

"He must ensure Centrelink services — online and in person — are working now when Australians need them most."

People queued around the block in Brookvale, NSW. ( ABC News: Tim Ayliffe )

The Government's latest $66 billion stimulus package includes help for casual workers, sole traders, and small businesses.

Some asset tests for welfare payments are being waived.

Small businesses can apply for grants of up to $100,000, and the Jobseeker Payment is being doubled.

Taking into account the first round of stimulus measures, and those announced by the Reserve Bank this week, the total economic assistance package is now worth $189 billion, according to the Government.

That is equivalent to 9.7 per cent of Australia's gross domestic product.

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