A number of Government websites were targeted in cyber attacks overnight as local and European election vote counting continues.
Pro-Russian hacking groups are believed to be behind the coordinated attack.
The National Cyber Security Centre said the impact from the 'DDoS' attacks was minimal.
A Distributed Denial of Service (DDoS) attack is designed to force a website, computer, or online service offline. This is accomplished by flooding the target with many requests, consuming its capacity and rendering it unable to respond to legitimate requests.
The websites for Irish Rail, Bus Éireann, Transport for Ireland, the Houses of the Oireachtas, the Leap Card, and voter registration portal Voter.ie were all targeted, The Sunday Times reports.
By James Cox & Beat News
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