NHS forced to turn away patients amid cyberattack chaos

Hospitals across the country have been forced to cancel and delay patient operations after a global cyberattack crippled computer systems.

At least 30 health service organisations in England and Scotland have been affected by the hack attack, while others shut down servers as a precautionary measure to avoid contagion.

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People have been advised to avoid going to accident and emergency unless absolutely necessary, while staff had to resort to using pen and paper and use their own mobile phones after IT networks failed.

Across the world, up to 99 countries have reportedly been targeted by the attack that locked up computers and held users' files for ransom, with Russia appearing to be hardest hit.

Home Secretary Amber Rudd, who is chairing an emergency COBRA meeting to discuss the crisis, could not confirm if all patient files had been backed up.

She said it was "disappointing" some hospitals had been using the outdated Windows XP operating system, despite being instructed not to by the Health Secretary Jeremy Hunt.

Ms Rudd told Sky News: "Where the patient data has been properly backed up, which has been in most cases, work can continue as normal because the patient data can be downloaded and people can continue with their work."

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However, NHS sources believe there is no evidence of "patient harm" as a result of the malware attack.

NHS Digital, which runs the health service's IT systems, has said 16 hospital trusts are among the organisations affected, of which five "major trusts" have been impacted seriously, sources told Sky News.

An alleged hacker unconnected to the incident told Sky News the attack could spread to nearly every country in the world.

"I'm sad to say that this is probably only just beginning; administrators are in for a very difficult weekend," Lauri Love said.

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The National Cyber Security Centre is working on a major operation in response to the attack, which it said targeted "thousands of organisations and individuals".

"We are very aware that attacks on critical services such as the NHS have a massive impact on individuals and their families, and we are doing everything in our power to help them restore these vital services," said Ciaran Martin, the body's chief executive.

He added teams were "working round the clock" to restore service and contain the damage.

Mr Martin urged the public to reduce the risk of an attack by making sure the security software patches are up to date, by running proper anti-virus software and, most important of all, by backing up data.

"You can't be held to ransom if you've got the data somewhere else," Mr Martin told Sky News.

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NHS Digital, which runs the health service's IT systems, said it had identified the malware software known as WannaCry, also known as Wanna Decryptor, which appears to be requesting $300 from victims to decrypt their computers.

The malicious software behind the attack appeared to exploit a vulnerability in the Windows system, which was recently made public by the Shadow Brokers hacker group.

Microsoft said it had already issued software patches for the loopholes, but many companies and individuals had not yet installed the fixes yet or were using older, obsolete versions of Windows.

The hack also exposed serious vulnerabilities at the NHS.

Last year a Sky News investigation discovered that NHS trusts were putting patients at risk, with seven trusts spending nothing on cybersecurity in 2015.