Ransomware takes down hospitals, businesses in at least 2 countries

Also, the hack happened four weeks before a British parliamentary election in which national security and the management of the state-run National Health Service (NHS) are important campaign themes.

Spain, meanwhile, took steps to protect critical infrastructure in response to the attack.

Cyber security experts argue that the NSA first discovered the vulnerability that has caused chaos almost around the world.

In a statement, Avast Threat Lab said it has observed a massive peak in WanaCrypt0r 2.0 attacks, with more than 36,000 detections, so far.

Ransomware is a debilitating form of malware that breaks into a system and locks users out by encrypting all of their files.

"There's nothing you can do but pay once you're hit", Camacho said.

By then, it was already too late.

NHS England has declared a major incident.

Other victims of the attack include Spanish telecom giant Telefónica, which said the infection was limited to some of its computers on an internal network and did not affect clients or services. Spain's Telefónica and Russia's MegaFon were among the largest of the businesses targeted.

A number of hospitals in Britain and firms in Spain were hit by separate large-scale cyber attacks yesterday.

Health workers reported being locked out of their systems and seeing messages demanding ransom payment to regain access.

At least 16 organizations connected to the National Health Service (NHS) in England reported being affected. Officials later updated that number to at least 25.

A malware called Wanna Decryptor was used in the attack, which encrypts files on a user's computer, blocking them from view. When asked to confirm that Wana Decryptor has struck in the USA, and at what scale, Acting Deputy Press Secretary Scott McConnell did not provide specifics.

Previous year we investigated cybersecurity in the NHS.

Nottingham CityCare Partnership has been affected and issued a statement to the Nottingham Post which said: "We have been affected and all IT systems have been shut down". Up-to-date backups make it possible to restore files without paying a ransom.

Doctors at some surgeries were forced to use pen and paper to record patient details following the attack, local media reported.

Mrs May said: "This is not targeted at the NHS, it's an global attack and a number of countries and organisations have been affected. NHS Digital are investigating the incident and across the NHS we have tried and tested contingency plans to ensure we are able to keep the NHS open for business", she said.

Services in London, the central city of Nottingham, and the counties of Hertfordshire and Cumbria were affected, according to the BBC.

Hospitals in areas across the United Kingdom found themselves without access to their computers or phone systems.

A bit to the south, in the seaside town of Southport, images on Twitter showed ambulances backed up outside the town's hospital. The only people suffering are people that need emergency care.

Spain's National Cryptology Centre confirmed that an attack had been launched "against various organizations" in the country and other companies were taking preventative measures.

As the scale of the security breach became clear on Friday afternoon, ambulances were diverted and patients told to avoid some A&E departments.

The attack hit Britain's health service, forcing affected hospitals to close wards and emergency rooms. Most of the affected hospitals were in England, but several facilities in Scotland also reported being hit.

Several employees of MegaFon, one of the largest cellphone operators in Russian Federation, said its systems were attacked by malware like that used against the NHS, the news website reported.

Like this