In the case of any individual who dies while in active service as a member of the armed forces of the United States, if the death occurred while serving in a combat zone, as that term is defined by the Internal Revenue Code of 1986, or as a result of wounds, disease, or injury incurred while so serving, any tax imposed by this article:

(1) Shall not apply with respect to the taxable year in which falls the date of his death or with respect to any prior taxable year ending on or after the first day he served in a combat zone after June 24, 1960;

(2) For a taxable year preceding those specified in paragraph (1) of this Code section which is unpaid at the date of his death including, but not limited to, interest, additions to the tax, and additional amounts shall not be assessed. If assessed, the assessment shall be abated. If any such amount is collected, it shall be credited or refunded as an overpayment.