Fears of fresh cyber attacks as workers return to the office on Monday morning
Ransomware has hit more than 200,000
Europol chief warns of further disruption
Fears as workers return to the office after weekend
The threat from the cyber attack that crippled international services "will continue to grow" as people return to work, the head of Europol warned.
Since Friday's breach more than 200,000 victims - including the NHS in the UK - across 150 countries have been infected by the Wanna Decryptor ransomware, also known as WannaCry.
Speaking to ITV's 'Peston on Sunday', Europol director Rob Wainwright said the attack was indiscriminate across the private and public sectors.
"At the moment we are in the face of an escalating threat, the numbers are going up. I am worried about how the numbers will continue to grow when people go to work and turn on their machines on Monday morning.
"The latest count is over 200,000 victims in at least 150 countries. Many of those will be businesses, including large corporations."
Meanwhile, HSE chief Tony O'Brien urged caution. He tweeted: "The cyber threat is not over. Maximum vigilance needed in days ahead."
- Read more: Cyber security expert: 'Criminals don't care about nationality, all countries should be worried about ransomware'
Last night, the Government warned of possible disruption to IT services today.
"IT departments across Government and the private sector have been working over the weekend to upgrade IT equipment and to apply patches to deal with the vulnerability that this malware exploits," said a Government spokesman.
"Most of these works will be completed over the weekend, but in some cases there will be minor disruption to IT services as works are completed and systems are brought back online. The impact of this on Ireland has been limited thus far, but this may change as the situation evolves."
Meanwhile, staff at the HSE have been advised not to log in to HSE systems for two hours after they have physically switched their computers on.
"As staff go back to work tomorrow, the HSE is advising all of its staff to turn on their computers but do not log on for a full two hours," said the Government spokesman. "This will allow the anti-virus capability to become active while still allowing the network to remain protected. Each health building will have an IT representative to provide assistance in the morning."
The spokesman said that the National Cyber Security Centre in the Department of Communications, Climate Action and Environment is "monitoring the situation on an ongoing basis".
Organisations across the globe, including investigators from the UK's National Crime Agency, are now working non-stop to hunt down those responsible for the ransomware.
Meanwhile, health authorities are racing to upgrade security software amid fears hackers could exploit the same vulnerability with a new virus.
- Read more: 'One of the biggest attacks in history': Six things you need to know about the worldwide ransomware hit and what it means for Ireland
There have been calls in Britain for an inquiry into the circumstances surrounding Friday's major incident, with the UK government and NHS chiefs facing questions over their preparedness and the robustness of vital systems.
"We have been concerned for some time. The healthcare centres in many countries are particularly vulnerable. They are processing a lot of sensitive data," said Mr Wainwright.
Ciaran Martin, chief executive of the UK's National Cyber Security Centre, warned there could be a fresh wave of victims today.
"We have not yet seen Friday's attack reoccur, there's been no new wave of attacks.
"On Monday morning at the start of the new working week, it's likely that successful attacks from Friday that haven't yet become apparent will become apparent," he said.
"And also existing known infections can spread."
A British cyber expert was hailed an 'accidental hero' after he registered a domain name that unexpectedly stopped the spread of the virus, which exploits a vulnerability in Microsoft Windows software.
The anonymous specialist, known only as MalwareTech, prevented more than 100,000 computers across the globe from being infected.
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