Genesis 19:21-25
19:21 “Very well,” he replied, “I will grant this request too and will not overthrow the town you mentioned.
19:22 Run there quickly, for I cannot do anything until you arrive there.” (This incident explains why the town was called Zoar.)
19:23 The sun had just risen over the land as Lot reached Zoar.
19:24 Then the Lord rained down sulfur and fire on Sodom and Gomorrah. It was sent down from the sky by the Lord.
19:25 So he overthrew those cities and all that region, including all the inhabitants of the cities and the vegetation that grew from the ground.