"SECTION 248. Civil Penalties. -

"(A) There shall be imposed, in addition to the tax required to be paid, a penalty equivalent to twenty-five percent (25%) of the amount due, in the following cases:

"(1) Failure to file any return and pay the tax due thereon as required under the provisions of this Code or rules and regulations on the date prescribed; or

"(2) Unless otherwise authorized by the Commissioner, filing a return with an internal revenue officer other than those with whom the return is required to be filed; or

"(3) Failure to pay the deficiency tax within the time prescribed for its payment in the notice of assessment; or

"(4) Failure to pay the full or part of the amount of tax shown on any return required to be filed under the provisions of this Code or rules and regulations, or the full amount of tax due for which no return is required to be filed, on or before the date prescribed for its payment.

"(B) In case of willful neglect to file the return within the period prescribed by this Code or by rules and regulations, or in case a false or fraudulent return is willfully made, the penalty to be imposed shall be fifty percent (50%) of the tax or of the deficiency tax, in case any payment has been made on the basis of such return before the discovery of the falsity or fraud: Provided, That a substantial underdeclaration of taxable sales, receipts or income, or a substantial overstatement of deductions, as determined by the Commissioner pursuant to the rules and regulations to be promulgated by the Secretary of Finance, shall constitute prima facie evidence of a false or fraudulent return: Provided, further, That failure to report sales, receipts or income in an amount exceeding thirty percent (30%) of that declared per return, and a claim of deductions in an amount exceeding thirty percent (30%) of actual deductions, shall render the taxpayer liable for substantial underdeclaration of sales, receipts or income or for overstatement of deductions, as mentioned herein.