More than 10 million Australians were without phone and internet services today due to an unexplained outage at the country’s second largest telecommunications provider, causing chaos in transport, payments and the health system.

The fault was detected today at around 4 am (19:00 local time of Tuesday Greek time) and by 17:30 local time today the damage had been repaired.

For most of the day about 40% of the population of Australia who are customers of the company Optus could not use smartphones, internet or even fixed lines.

“There is no indication” that the damage is the result of hacking or cyber-attack, the company’s general manager Kelly Bayer Rosmarin said on state broadcaster ABC.

“Our team is still looking into all possible possibilities. We have made a number of guesses and none of them, which we have checked and acted upon, have resolved the underlying problem,” he added.

“Absolute disgrace”

Dozens of hospitals were not accepting phone calls and landlines on the Optus network could not call the emergency services. The New South Wales poison control center’s phones were also down.

Chaos reigned in Melbourne during rush hour after the breakdown also affected train traffic, according to the management company, Metro Trains Melbourne.

“Our teams are working to restore services as quickly as possible,” an Optus spokesperson said. “Optus sincerely apologizes to its customers.”

Australian Communications Minister Michelle Rowland said the problems were caused by “serious damage” to a “fundamental” part of Optus’ network.

The outage “has a huge impact on mobile and landline services and the internet services of Optus customers,” he stressed, asking the company to “react accordingly” to the situation.

The Australian Telecommunications Union called it an “absolute disgrace”. implying that the damage is linked to the company’s recent job cuts.

Mark Gregory, a researcher at the Royal Institute of Technology in Melbourne, for his part estimated that this failure proves that there are fundamental problems in the Australian telecommunications network.

The incident comes about a year after the personal data of more than nine million Optus customers was stolen in a cyber attack.