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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Samantha Baldwin, 42, and her sons Louis Madge, nine, and Dylan Madge, six, haven't been seen for two days.
Police want to speak to anyone who knows what Thomas Rhodes was doing the night before he was found
Alexander Palmer, of Selborne Street, was found guilty of six counts of indecent assault and two counts of gross indecency with a child.