Cyber security experts believe the Petya malware attack may have been orchestrated in Russia.
Around 230 thousand computers in 130 countries have been affected by the attack that blocks computer files.
READ MORE:Â Cyber attack hits New Zealand
Cyber security expert Rob Pritchard told Rachel Smalley wherever the attack originated from, Ukraine has been the main target.
"They say speculatively that one can imagine this was something that was done by someone who wanted to cause destruction to the Ukraine for some reason.'
Pritchard said the reason for the attack remains unknown.
"It didn't really seem as if the aim of this was to make lots of money. It could just be criminals or it could be patriotic hackers."
LISTEN ABOVE AS ROB PRITCHARD SPEAKS WITH RACHAEL SMALLEY
Take your Radio, Podcasts and Music with you