Britain's National Health Service, one of the biggest state-run systems in the world, has suffered a significant cyber attack across its IT network Friday that has hit phone, computer and communications and forced the cancellations of surgeries around the country. 

The NHS, as it is known in Britain, has said they're investigating the system failure, which comes only hours after Spain's Telefonica SA, the country's biggest carrier, said it was hit by a "massive ransomware attack" that also affected other companies and organisations in Europe's fourth-largest economy.

Spain's national cryptology center, a branch of the country's intelligence service, said the attack was aimed at Window operating systems by "encrypting all its archives and all the connected units inside the network, and infecting the rest of the Windows systems inside the network."

Telefonica was the only company to confirm it had been attacked, saying it had been suffered a "cybersecurity incident" affecting the personal computers of "some" employees.

Earlier this week, Microsoft Corp.(MSFT) - Get Report  released an urgent update to stop hackers taking control of computers after a bug was discovered in its anti-malware software that allowed hackers to exploit by sending an infected email, instant message or getting the user to click on a web browser link.

Windows 8, 8.1,10 and Windows Server operating systems were affected by the bug, Microsoft said.