A Facebook post for staff said: "The information included names, addresses and bank account details of colleagues. This affects colleagues from all levels of the organisation.
"We are taking this extremely seriously. Dalton Philips is leading the response."
But one person commented on the site: "I haven't been informed of this and shouldn't have to read it on here."
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The latest forecast for the Calendar region from Kerrie Gosney
A man who filmed himself kicking a rabbit across a field while drunk has been handed a suspended jail sentence and fined £7,000.
Predominantly dry over the coming few days with variable cloud & some sunshine. Cool start but daytime temperatures should recover a little