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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A second half strike from the Senegalese international saw Hull City beat Sheffield Wednesday 1-0. Chris Dawkes reports from Wembley.
Part of the breathtaking Poppies sculpture from the Tower of London has gone on display today at Lincoln Castle.
Chris Dawkes has the half-time match report from Wembley with Hull City drawing 0-0 with Sheffield Wednesday