The Boston Globe reports that approximately 1,800 checks that were sent to the Internal Revenue Service this spring are missing. The checks, which were payable to the Internal Revenue Service, were for first quarter estimated tax payments, tax filing extension requests, and 2000 federal income tax returns.

The disappearance of the checks was determined after about 1,800 taxpayers reported that checks written and sent to the IRS earlier this spring had not yet cleared their banks.

The checks in question were sent to a post office box in Pittsburgh, PA, and were to be processed by Mellon Bank and deposited in a U.S. government account. Records on certified mailings indicate the IRS received the checks. Where the checks went after they were removed from the envelopes in which they were mailed is yet to be determined.

The Treasury Department's inspector general is looking into the matter. Meanwhile, the IRS would like taxpayers who made tax payments in April that haven't yet cleared to call the IRS at 1-800-829-1040. The service is recommending that affected taxpayers stop payment on the check and request a Form 8546 for reimbursement of stop payment fees.