The Justice Minister has urged anyone who is contacted about their medical information to contact the Gardaí.
Those behind the HSE cyberattack are expected to release personal information in the coming days.
Minister Heather Humphreys says anyone who is contacted about their information and asked to pay a ransom should contact Gardaí and not pay any money.
She says she is holding daily meetings as part of the ongoing work to investigate those behind it.
Speaking in Glaslough she said Gardaí are working with international agencies:
The decryption key for the HSE cyber-attack is undergoing a detailed assessment to determine whether it's safe to use.
The Government says the key arrived "unprompted" yesterday evening and that no ransom was paid to the gang behind the attack.
It's also warning that should the key work, it doesn't mean the hackers won't proceed to publish data on the dark web.
An injunction has been secured to prevent anyone who obtains patient data from sharing it.