Al-Furqan 25:4

وَقَالَ ٱلَّذِينَ كَفَرُوٓا۟ إِنْ هَـٰذَآ إِلَّآ إِفْكٌ ٱفْتَرَىٰهُ وَأَعَانَهُۥ عَلَيْهِ قَوْمٌ ءَاخَرُونَ ۖ فَقَدْ جَآءُو ظُلْمًا وَزُورًا

Waqāla alladhīna kafarū in hādhā illā if'kun if'tarāhu wa-aʿānahu ʿalayhi qawmun ākharūna faqad jāū ẓul'man wazūran

And those who disbelieve say, "This [Qur’ān] is not except a falsehood he invented, and another people assisted him in it." But they have committed an injustice and a lie.