For interest-bearing accounts that are frozen for suspicious activity
Under what legal authority are you doing this? You customer could sue you for wrongful dishonor of any properly payable checks under the Uniform Commercial Code.
If you want to stop paying interest, you cite the appropriate clause of your account agreement that gives you the right to close an account at any time and close the account. Your Reg DD disclosure should already say what happens to accrued interest if an account is closed prior to interest being credited.
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