NSW Health and Illawarra Minister Ryan Park said the state government was undertaking a “comprehensive review” of all calls received by ambulance services during the outage, and urged confidence in Triple Zero services following the latest incident.

NSW Opposition Leader Mark Speakman called on Singtel to consider “whether those running the show are up to it”, and pushed for “assurances [that] this won’t happen again”.

“We’ve already seen people die, and today we hear of more triple-zero failures in the Illawarra over the weekend, and undoubtedly lives may have been put at risk,” Speakman said. “We still don’t know the full damage, and the errors are mounting.”

The telco is grappling with the fallout from its catastrophic Triple Zero outage earlier this month, which affected customers across South Australia, Western Australia and parts of NSW and has been linked to three deaths.

Optus is bracing for a wave of customer losses and long-lasting reputation damage after the outage, with industry insiders warning the telco’s credibility has been shredded and its governance failures exposed.

Rue has blamed human error by staff in Australia and India for the “process breakdown”, finding that network engineers did not follow key steps undertaken while conducting similar upgrades in the past.

Optus chief executive Stephen Rue.

Optus chief executive Stephen Rue.Credit: Sitthixay Ditthavong

“It should be reiterated that the issue occurred because this time there was a deviation from established processes,” Rue said last week.

“To be very clear: Optus is accountable for the operations of its network.”

Optus has appointed corporate veteran Kerry Schott to lead an independent inquiry into the outage.

Questions are now turning to Singtel, which cut investment in the Australian mobile network by $237 million last year. Singtel is 51 per cent owned by investment giant Temasek, which is fully owned by the Singaporean government. Singtel wholly owns Optus.

Yuen Kuan Moon is jetting to Australia to meet with Wells, Rue and Optus chair John Arthur on Tuesday.

Federal Minister for Communications Anika Wells warns Optus can expect significant fines.

Federal Minister for Communications Anika Wells warns Optus can expect significant fines.Credit: Kate Geraghty

“Singtel takes this matter seriously and will extend full co-operation to the Australian government and authorities to address the Optus issue,” a Singtel spokesperson said.

Nerida O’Loughlin, chair of federal telecommunications regulator the Australian Communications and Media Authority, has said she would investigate whether Singtel and Optus had invested enough in the networks to ensure they could provide reliable emergency service connectivity.

The company on Wednesday was also ordered by the Federal Court to pay a $100 million penalty – an amount it had previously agreed with the consumer watchdog – for “unconscionable” conduct including selling handsets to people with intellectual disabilities and suffering financial hardship.

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