A new virus displaying behavior markedly similar to WannaCry is attacking Russian and Ukrainian company computers.

According to local reports, the Petya virus is locking computers and demanding payment of a $300 ransom in Bitcoins to regain control.

“It blocks computers and demands $300 in bitcoins,” specialist Group-IB stated to RIA Novosti.

“The attack happened from around 2pm. Judging from photographs, it is the cryptolocker [ransomware] Petya. The way it is spreading through local networks is similar to the WannaCry virus.”

WannaCry’s Bitcoin ransomware demands caused havoc worldwide in May after employees were locked out of computers in a range of locations.

The attack exposed antiquated equipment and lax security commonplace in many major corporate and public sector computer networks, with victims such as the UK National Health Service particularly vulnerable due to the extensive use of unsupported Windows XP software.

Even India’s ATM network was feared to be a likely target.

Petya has already claimed major Russian prizes such as gas giants, as well as Ukrainian postal service Novaya Pochta.

The company stated in a Facebook post that it was temporarily unable to service customer requests due to the Petya attack.