*There are reports of major IT network outages across the world tonight

*New Zealanders are reporting issues with banking and transport services, including delayed flights

*Shops and supermarkets checkout systems have gone down and some Woolworths stores have closed

*People fuelling up their cars this evening have been told to use cash

*The issue is believed to have been caused by an update by cybersecurity firm CrowdStrike

A global IT network outage is causing chaos tonight, downing banking services, disrupting flights, preventing supermarket purchases and causing havoc for public transport commuters.

There are reports of outages involving some nationwide bank payment systems this evening, as well as global network problems with television and Microsoft services.

The Federal Aviation Administration has grounded flights from several major US carriers, including Delta, United and American Airlines, due to communication issues.

Herald readers have spoken of queues at supermarkets due to checkouts going down and commuters being unable to tag on or tag off with Auckland Transport HOP cards.

Issues with debit and credit cards including ASB, ANZ and Kiwibank are being reported.

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ANZ Tap n Pay and Visa payWave are also reported to be down.

The Herald has tried approaching the Banking Association for comment.

ASB confirmed several of its services were down due to “an external vendor issue” which had hit telecommunications and banking companies worldwide.

BNZ and Westpac told the Herald they were not experiencing any issues with their internet banking or payment systems.

Herald readers have reported problems at supermarket checkouts tonight and similar problems at other shops.

A person texted NZME to say Auckland Transport’s tag-on, tag-off terminals are not working either.

The Herald understands Jetstar has been impacted by the global IT glitch.

A Herald reader says Jetstar announced over the loudspeaker in Wellington Airport it was delaying flights due to the outage.

Christchurch International Airport said flights may be disrupted due to IT issues there.

Air New Zealand told the Herald it was not aware of any operational impacts at this stage.

Auckland Airport said all systems are operating as normal and there have been no check in issues.

A police spokeswoman said they were unaware of any issues with their services, as did Fire & Emergency NZ.

Television channels, including Sky News Australia, have also gone off air, with the Daily Mail reporting it had been hit “with an ongoing technical issue”.

There have been reports of computers running on Microsoft Windows having crashed worldwide, with users saying their computers were displaying a blue screen of death (BSOD).

The Wall Street Journal tweeted that Microsoft was reporting a service outage for its Microsoft 365 apps and services, affecting businesses and users across the world.

Windows computers are reportedly showing BSOD errors across various different sectors, including supermarkets, banks and broadcasters.

Reports of outages have been made online via the Downdetector website, showing issues with Microsoft 365 services.

The issue is reported to be linked to an update by cybersecurity company CrowdStrike.

CrowdStrike says its “engineering teams are actively working to resolve this issue”.

Sky say ‘Crowdstrike’ has gone down.

“Was bloody chaos down at the supermarket,” a Herald reader wrote on social media.

“The self checkouts all started running into errors and resetting themselves too. By the time I got to the front of the line there were only two or three that remained working.”

Another person wrote: “Curious about the reports of BSOD (blue screen of death) crashes with computer systems. I went into Chemist Warehouse today and Woolies and both had at least one computer system with a BSOD problem, with the Chemist Warehouse one stuck in a reboot and BSOD loop. Weird.”

A New Zealander holidaying in Fiji told the Herald he has been unable to access his funds through ASB bank for the last two hours and was not able to reach the bank for answers.

Another Herald reader says Kiwibank cards and eftpos are not working tonight.

Kiwibank said it was aware of an issue logging into internet banking and app.

- More to come