Visitors to the MetService website this week may have been exposed to a computer virus, after its ad server was hacked.
The weather forecaster today confirmed that at 8pm yesterday its web support team identified an issue with its ad server and immediately shut it down.
"We now know that the ad server was compromised by a malicious attack,'' MetService said.
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This came as MetService reported record number of visitors to the site because of the severe polar blast lashing the country this week.
It was estimated the site was at risk for about four hours.
The source of the attack was traced to an overseas IP address, "but this is sure to be merely the start of a long trail that may never lead back to the culprit'', MetService said.
The site was now safe to access.