The council for Comhairle nan Eilean Siar, also known as the Outer Hebrides — the chain of islands off the west coast of Scotland — has said it may cost up to £500,000 to repair its computer systems following a ransomware attack last November.

An update about the response to the incident from the local authority, which governs more than 26,000 people, was delivered Tuesday in Stornoway, the largest town in the Outer Hebrides.

According to the council’s chief executive Malcolm Burr, there is currently no evidence that any data stored on the compromised servers has been published online. Burr added that while progress is being made to replace the systems impacted by the attack, it could be another six months before things return to normality.

The leaders of the council said they were seeking additional financial support to cover the costs of the IT system rebuild, which could run as high as £500,000 (about $624,500).

The ransomware attack has even interrupted the local authority’s council tax billings, which typically amount for around one-fifth of a Scottish council’s budget to be spent on services, including social care. The additional costs to the council follow the Scottish government cutting its budget by almost £1.5 million for this financial year.

The attack on Comhairle nan Eilean Siar was one of a record number of ransomware attacks targeting local authorities across the United Kingdom in 2023. In total, 118 were reported to the data protection regulator, an increase of more than 800% on the 13 reported the year before.

The sharp rise in attacks last year has prompted onlookers to urge the British government to put more money behind operations to disrupt ransomware gangs instead of just relying on the existing approach of resilience.

Earlier this year, a parliamentary committee accused the government of taking the “ostrich strategy” by burying its head in the sand over the “large and imminent” national cyber threat posed by ransomware.