فَإِنۡ أَعۡرَضُواْ فَقُلۡ أَنذَرۡتُكُمۡ صَٰعِقَةٗ مِّثۡلَ صَٰعِقَةِ عَادٖ وَثَمُودَ ١٣
But if they turn away, then say, "I have warned you of a thunderbolt like the thunderbolt [that struck] ʿAad and Thamūd.
Translation: Saheeh International (English)
Each word's meaning and sound
So if these people turn away from bringing faith in what you have brought, then say to them: “I have warned you of a punishment that will fall upon you, like the punishment that fell upon the people of Hud, the ‘Ād, and the people of Saleh, the Thamūd, when they rejected their messengers.
Al-Mukhtasar in interpreting the Noble Quran