What is the required number of witnesses for establishing the act of Zina (for which the prescribed punishment/Hadd is due)?

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The act of Zina that necessitates the prescribed punishment (Hadd) requires the testimony of four witnesses, according to the consensus of the scholars. This is based on the explicit text of the Quran: {And those who accuse virtuous women and then do not bring four witnesses, flog them eighty lashes} (Quran 24:4). This requirement extends to sodomy (liwat) and anal intercourse with a woman, as both are considered Zina.