Surah Al-Hujurat, ayah 6

49:6

يَٰٓأَيُّهَا ٱلَّذِينَ ءَامَنُوٓاْ إِن جَآءَكُمۡ فَاسِقُۢ بِنَبَإٖ فَتَبَيَّنُوٓاْ أَن تُصِيبُواْ قَوۡمَۢا بِجَهَٰلَةٖ فَتُصۡبِحُواْ عَلَىٰ مَا فَعَلۡتُمۡ نَٰدِمِينَ ٦

Yā'ayyuhal-ladhīna āmanū in jā'akum fāsiqu binaba'in fatabayyanū an tusībū qawmā bijahālatin fatusbihū 'alā mā fa'altum nādimīn

O you who have believed, if there comes to you a disobedient one with information, investigate, lest you harm a people out of ignorance and become, over what you have done, regretful.