(Bloomberg) -- Ireland’s Department of Health is grappling with a new cyber attack as the country’s health service faces a third day of disruption after hackers forced the shutdown of its computer systems.

The Department of Health has been hit by an attack similar to the ransomware one carried out last week on the country’s Health Service Executive, RTE News said on Sunday, adding that the department has also shut down its systems. The Department of Health could not immediately be reached for comment outside of normal office hours.

“There are cancellations across all outpatient services with widespread cancellation of radiology services,” the HSE said on its website on Sunday. Most virtual appointments will go ahead as planned but some have been scrapped, while others may be handled by phone, it said.

COVID-19 vaccination appointments and testing are underway, but there may be some delays in getting results back, the service said. Contact tracing is also operating, though it may take longer than usual, it said. National coronavirus infection case numbers haven’t been published since last Thursday.

Ireland’s health service shut down its computer systems last week amid what it described in a tweet on Friday as a “significant” cyberattack. The attackers exploited a computer vulnerability that wasn’t previously known using so-called Conti ransomware, Anne O’Connor, the HSE’s head of operations, told RTE Radio. The incident came in a week that saw the largest gasoline pipeline in the U.S. taken offline for five days following a cyber attack.

Ireland’s Prime Minister Micheal Martin has publicly said the country will not pay any ransom to hackers.

“We are at the very early stages of fully understanding the threat, the impact, and trying to contain” the attack, Irish health service Chief Executive Officer Paul Reid told RTE Radio.

Ireland’s National Cyber Security Center is “engaging with the European Union and other international partners to share information on this incident and to ensure that the HSE has immediate access to international cyber supports,” the communications ministry said in an emailed statement.

In 2017, the U.K’s National Health Service was infiltrated by ransomware, affecting 45 organizations and forcing hospitals to turn away patients.

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