Identity Theft Loan

I was a victim of identity theft and my personal details were used to apply for a loan with this institution. I notified their ***** department of this and provided them with all the requested information, as I knew nothing about the application, and it no time did they get in contact with me to confirm anything - apparently everything is simply done online - what a scary thought! I was advised that their ***** department will investigate and get back to me, but this never happened. So this morning I received a notification from my bank that a debit order from this institution was processed against my bank account, for what I can only assume is the commencement of the repayment of this loan - never did I authorize such a debit order and have no idea what the repayment terms are, seeing that I never in the first place did apply for this loan originally! Numerous e-mails to them to address this issue, has also gone unanswered. I need them to sort this out ASAP!!!