Telstra outage sparks security concerns as Barnaby Joyce calls for investigation into ...

One Nation MP Barnaby Joyce has called for a “diligent process” to determine whether the Telstra outage was linked to foreign interference involving China.

One Nation MP Barnaby Joyce has called for a “diligent process” to establish whether Telstra’s network disruption may have involved Chinese interference.

Telstra has said it is still trying to determine the cause of the failure, which affected calls, mobile data and some Triple Zero services.

Reports of the problem began emerging shortly after 3am on Wednesday, with users in Sydney, Melbourne and other capital cities saying they had lost mobile connectivity.

Mr Joyce said while he did not want to appear "paranoid", the government needed to probe any links to Beijing after China fired a test missile into the South Pacific earlier this week.

“I don’t want to be paranoid or a conspiracy theorist, but we know there is the capacity for China to affect that sort of software and that sort of network,” Mr Joyce told Sky News.

“It’s better to be cautious and to have things cleared up than to just dismiss that out of hand … I do think (there needs to be) a diligent process.”

Mr Joyce questioned whether it was “just a coincidence” that the intercontinental ballistic missile launched by China went into the Pacific two days before the outage.

In an update just before 10am on Wednesday, Telstra confirmed that almost 90 per cent of its mobile network was back online and the company would continue to investigate what caused the failure.

Customers of other mobile providers that operate on Telstra's network, including Everyday Mobile, Aldi, Tangerine, Boost, and Belong had also reported outages.

In a joint statement, Communications Minister Anika Wells and Emergency Management Minister Kristy McBain urged Australians not to make "test" Triple Zero calls.

"The core Triple Zero system remains operational, with connected calls flowing as expected from carrier networks to the Emergency Call Person (ECP), and on to state and territory emergency services dispatchers," the said.

"However, the Triple Zero Custodian has advised that some callers were unable to connect to the ECP, and that these are being investigated by Telstra.

All telcos, including Telstra, have strict requirements in relation to welfare checks for disconnected Triple Zero calls, and the Triple Zero Custodian is in regular communication with Telstra to receive updates on the progress and outcomes of these checks.

"If you need to call Triple Zero and can't get through, it is recommended that you use another device, a landline or Wi-Fi calling.

"It is very important that people do not make 'test' calls to Triple Zero - please only call 000 if there is an emergency."

The government confirmed the Australian Communications and Media Authority will conduct a full investigation into the outage, and Telstra will need to account for how and why this outage occurred.

"The key priorities for today are to get people back online and ensure any welfare checks are completed urgently," the ministers said.

Speaking at a media conference, Telstra chief financial officer Michael Ackland apologised to customers, describing the outage as a significant disruption.

He insisted the company was working as quickly as it could to restore the remaining services.

Mr Ackland said the fault had been traced to network "nodes" responsible for synchronising time across Telstra's mobile network.

He said engineers had already restored several of the affected nodes, but warned it would take time for the repairs to flow through to the thousands of servers operating across the network.

Mr Ackland said emergency calls were handled differently to ordinary mobile traffic and had not experienced the same widespread disruption.

“Triple zero calls follow different settings in our network and therefore they were not impacted in the same way,” he said.

However, he confirmed Telstra was investigating a "small number" of reported issues and had already started conducting welfare checks.

“We have seen a small number of reports that we are investigating,” he said.

“As part of our standard process... we conduct welfare checks when any call to triple zero fails and we've been doing this.”

He urged Australians not to test the emergency number while the investigation continued.

Earlier, Western Australia Police and New South Wales Police said Telstra customers might have issues calling Triple Zero.

Mr Ackland said Telstra was still determining exactly how the network issue affected those services.

“At this stage we have nothing to indicate malicious activity,” Mr Ackland said.

“We've been in with all regulators and government agencies to that effect.

“But we continue to investigate, we continue to remain curious and explore every avenue.”

While Telstra has not confirmed how many customers were affected, Mr Ackland indicated the number was likely in the thousands.

The company has also left open the possibility of compensation once services are fully restored.

⚠️ We’ve made good progress restoring services, with just under 90% of calls and data now flowing successfully across the network. Our teams are working as quickly as possible to restore remaining services and get all customers back online. (1/2)

Mr Ackland said there was no evidence to suggest that Wednesday's disruption was linked to "malicious activity".

"At this stage we have nothing to indicate malicious activity and we've been in with all regulators and government agencies to that effect," he said.

"But we continue to investigate, we continue remain curious and explore every avenue, but have nothing on that."

In Victoria, the outage has affected V/Line regional train services.

In NSW, a transport spokesperson said there were no known impacts to Sydney Metropolitan services or Opal systems.

"We are monitoring impacts to regional rail services, with some NSW TrainLink services, including the Melbourne XPT, experiencing delays due to telecommunications-related issues," the spokesperson said.

"Customer communications may also be affected while the outage continues.

"We will provide further updates as more information becomes available."

Earlier, a statement from WA Police said it was aware of some issues with Telstra users being able to reach Triple Zero.

“A Telstra outage is currently affecting customers nationwide, impacting their ability to make phone calls, including calls to Triple Zero from Telstra services,” the statement said.

“If you have a vulnerable family member, friend, neighbour or co-worker, consider offering support during the service disruption.

"If you are affected and do not have access to an alternative mobile or landline service, police recommend making arrangements with a neighbour, family member, or friend so you can access a working telephone in an emergency."

The New South Wales Police Force also warned Telstra customers might experience issues calling Triple Zero.

"Triple Zero systems are not affected, but you may not be able to reach Triple Zero if you are calling from a Telstra device," NSW Police said in a statement.

"If you try to call Triple Zero and can’t get through, we recommend using another device, a landline or Wi-Fi calling.

"Telstra will provide updates on the network outage as their tech teams work through a fix."

The NSW Police Force understands a Telstra outage is affecting some network devices. Triple Zero systems are not affected, but you may not be able to reach Triple Zero if you are calling from a Telstra device. If you try to call Triple Zero and can’t get through, we recommend…

Earlier, a Telstra spokesman said the issue was affecting some customers' mobile calls and data connection, but fixed internet services like NBN had not been affected.

“We’re looking into an issue affecting some mobile calls and data connections,” the spokesman said.

“If you’re having trouble connecting, try again as it may work on a retry.

“We’re on it and will an update as soon as it is fixed."

Some users said their phones had switched to SOS-only mode, while others reported they were unable to access mobile data.

Social media quickly filled with users asking whether others were experiencing similar issues with Telstra.

Prime Minister Anthony Albanese told reporters that Australians are "entitled to get answers" after the nationwide Telstra outage.

Mr Albanese described the incident as "deeply concerning" while confirming the government is working with the telecommunications giant.

“This is deeply concerning and it’s very disruptive to people’s lives throughout the country,” he said.

“This is a national outage that has varied effects. Telstra are investigating and we are working with them.

“The Triple Zero custodian is in constant with Telstra and with emergency services and investigations are underway at this stage.

“None of this is acceptable because it is disruptive ... we’ll continue to engage here, but people are entitled to get answers, but they want answers that are accurate.”

Earlier, Minister for Regional Development and Emergency Management Kristy McBain said the federal government was closely monitoring the outage.

"The Australian government has been advised by Telstra that there is an outage affecting a large number of mobile calls and connections,” she said in a statement.

"We are also aware the issue is also affecting Victoria’s V/Line regional train services.

"We understand Telstra is working on resolving the issue, and arrangements are being made for affected rail passengers.

"Like all telcos, Telstra must notify customers and emergency services of any major outage.

"Australian phones are also required to fall back to other networks for 000 access."

Opposition Leader Angus Taylor has called on the Albanese government to “front up”, provide answers and deliver information the widespread Telstra outage.

“We need the government to front up,” Mr Taylor said at a media conference in Darwin.

He said the outage was a “matter of great concern”.

“We don’t know the answers – there are many questions that need to be asked," he said.

“The minister needs to front up and explain to Australians what has happened here.”

Speaking to Sky News on Wednesday morning, deputy Liberal leader Jane Hume said the issue needed to be approached in a "sensible and sober way".

"We know how disruptive a Telstra outage can be, but I don’t want to speculate what the problem could be. Let’s let Telstra do that, rather than politicians," she said.