The WannaCry cyber attack hit 200,000 victims – including the NHS – in at least 150 countries, the head of the European Union's police agency said.

“We are in the face of an escalating threat,” Europol Director Rob Wainwright told ITV’s Peston on Sunday programme, adding he feared the number would grow when people return to work on Monday.

He said what was unique about the attack was that the ransomware was used in combination with a “worm functionality”, so the infection spread automatically.

“The global reach is unprecedented. The latest count is more than 200,000 victims in at least 150 countries, and those victims, many of those will be businesses, including large corporations,” he said.

“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.”

Cyber-attack: MalwareTech on how he "accidentally" halted the spread of the ransomware

Organisations across the globe, including investigators from the National Crime Agency (NCA), are now working non-stop to hunt down those responsible for the ransomware.

The spread of the virus dubbed WannaCry – ransomware that locked up more than 100,000 computers – had slowed, cybersecurity experts said, but they warned that the respite may be brief.

New versions of the worm were expected, and the extent of the damage from Friday’s attack was still unclear.

​Microsoft released patches last month and on Friday to fix a vulnerability that allowed the worm to spread across networks, a rare and powerful feature that caused infections to surge on Friday.

Meanwhile health authorities are racing to upgrade security software amid fears hackers could exploit the same vulnerability with a new virus.

Everyone the Government blames for the NHS crisis – except themselves Show all 6 1 /6 Everyone the Government blames for the NHS crisis – except themselves Everyone the Government blames for the NHS crisis – except themselves The elderly “We acknowledge that there are pressures on the health service, there are always extra pressures on the NHS in the winter, but we have the added pressures of the ageing population and the growing complex needs of the population,” Theresa May has said. Waits of over 12 hours in A&E among elderly people have more than doubled in two years, according to figures from NHS Digital. Getty Everyone the Government blames for the NHS crisis – except themselves Patients going to A&E instead of seeing their GPs Jeremy Hunt has called for a “honest discussion with the public about the purpose of A&E departments”, saying that around a third of A&E patients were in hospital unnecessarily. Mr Hunt told Radio 4’s Today programme the NHS now had more doctors, nurses and funding than ever, but explained what he called “very serious problems at some hospitals” by suggesting pressures were increasing in part because people are going to A&Es when they should not. He urged patients to visit their GP for non-emergency illnesses, outlined plans to release time for family doctors to support urgent care work, and said the NHS will soon be able to deliver seven-day access to a GP from 8am to 8pm. But doctors struggling amid a GP recruitment crisis said Mr Hunt’s plans were unrealistic and demanded the Government commit to investing in all areas of the overstretched health service. Getty Everyone the Government blames for the NHS crisis – except themselves Simon Stevens, head of NHS England Reports that “key members” of Ms May’s team used internal meetings to accuse Simon Stevens, head of NHS England, of being unenthusiastic and unresponsive have been rejected by Downing Street. Mr Stevens had allegedly rejected claims made by Ms May that the NHS had been given more funding than required. Getty Everyone the Government blames for the NHS crisis – except themselves Previous health policy, not funding In an interview with Sky News’s Sophy Ridge, Ms May acknowledged the NHS faced pressures but said it was a problem that had been “ducked by government over the years”. She refuted the claim that hospitals were tackling a “humanitarian crisis” and said health funding was at record levels. “We asked the NHS a while back to set out what it needed over the next five years in terms of its plan for the future and the funding that it would need,” said the Prime Minister. “They did that, we gave them that funding, in fact we gave them more funding than they required… Funding is now at record levels for the NHS, more money has been going in.” But doctors accused Ms May of being “in denial” about how the lack of additional funding provided for health and social care were behind a spiralling crisis in NHS hospitals. Getty Images Everyone the Government blames for the NHS crisis – except themselves Target to treat all A&E patients within four hours Mr Hunt was accused of watering down the flagship target to treat all A&E patients within four hours. The Health Secretary told MPs the promise – introduced by Tony Blair’s government in 2000 – should only be for “those who actually need it”. Amid jeers in the Commons, Mr Hunt said only four other countries pledged to treat all patients within a similar timeframe and all had “less stringent” rules. But Ms May has now said the Government will stand by the four-hour target for A&E, which says 95 per cent of patients must be dealt with within that time frame. Getty Images Everyone the Government blames for the NHS crisis – except themselves No one Mr Hunt was accused of “hiding” from the public eye following news of the Red Cross’s comments and didn’t make an official statement for two days. He was also filmed refusing to answer questions from journalists who pursued him down the street yesterday to ask whether he planned to scrap the four-hour A&E waiting time target. Sky News reporter Beth Rigby pressed the Health Secretary on his position on the matter, saying “the public will want to know, Mr Hunt”. “Sorry Beth, I’ve answered questions about this already,” replied Mr Hunt. “But you didn’t answer questions on this. You said it was over-interpreted in the House of Commons and you didn’t want to water it down. Is that what you’re saying?” said Ms Rigby. “It’s very difficult, because how are we going to explain to the public what your intention is, when you change your position and then won’t answer the question, Mr Hunt”. But the Health Secretary maintained his silence until he reached his car and got in. Getty

There have been calls for an inquiry into the circumstances surrounding Friday’s major incident, with the Government and Health Secretary Jeremy Hunt accused of ignoring “extensive warning signs”, which could have prevented the unprecedented cyber attack from plunging the NHS into chaos.

A number of hospitals in England and Scotland were forced to cancel procedures after dozens of NHS systems were brought down in Friday’s attack.

Medical staff reported seeing computers go down “one by one” as the attack took hold, locking machines and demanding money to release the data.

Around a fifth of trusts were hit amid concerns networks were left vulnerable because they were still using outdated Windows XP software.

Among those affected by the virus was Nissan UK, but the car manufacturer said there had been no major impact.