We've recently had a number of customers call telling us they have received calls from people identifying themselves as being from our bank and asking for information. Often they already know the customer's account number. We close the customer's account and open a new one, but are there other things we should be doing? Does anyone have a check list or list of questions to ask the customer?
Thanks.

With these calls coming in inmultiples, I'd suggest a couple of things:

Get whatever information you can about the callers to determine if they are coming from the same place.

Review the activity on the affected accounts to see if you can identify a common point of comprimise. Did they all write checks to the same payee? Did they all have deposits in the same batch of teller work (yes, I know, it's painful to consider the possibility of an inside job- but until you can rule it out, you'll need to consider it).