Al-An'am - 6:131

ذَلِكَ أَن لَّمْ يَكُن رَّبُّكَ مُهْلِكَ الْقُرَى بِظُلْمٍ وَأَهْلُهَا غَافِلُونَ
[6:131]
This is because your Lord would not destroy towns unjustly while their people were negligent.
(The messengers were sent) thus, for thy Lord would not destroy for their wrong-doing men's habitations whilst their occupants were unwarned.
This is because thy Lord destroyeth not the townships arbitrarily while their people are unconscious (of the wrong they do).