The attack was initially thought to be the Petya ransomware, which was identified in 2016. It was deployed in a large-scale and coordinated attack against oil, power, telecommunications and financial companies in Russia and Ukraine, and is now reported to have spread to other countries including India and Spain. The attack is targeting major infrastructure in affected countries, including the Chernobyl nuclear power station, Danish shipping company Maersk, US pharmaceutical giant Merck and British advertising company WPP.

UPDATE 15:00 CEST pic.twitter.com/L5pBYvNQd3

— Maersk (@Maersk) June 27, 2017

Security experts are warning that the attack, which was already reported as the largest in Ukraine’s history, could be larger and more devastating than the Wannacry, cyber attack that spread across the world in May. The origins of Petya ransomware, and the details on how it has spread, are currently unknown.

The latest from @kaspersky researchers on #Petya: it’s actually #NotPetya pic.twitter.com/uTVBUul8Yt

— Kaspersky Lab (@kaspersky) June 27, 2017

Kaspersky, the world’s largest independent security company is now reporting that the ransomware is something not encountered before and is claiming it is not Petya, using the hashtag #NotPetya for the current attack.

The UK’s National Cybersecurity centre says it is ‘aware of global ransomware incident‘.

We’ll have more news and updates as they happen…