The main shock occurred at 20:57 CEST (18:57 UTC) on 21 August 2017, and was rated 3.9 Mw  or 4.2 mb  on the moment magnitude scale.

One woman died in Casamicciola Terme after being hit by rubble that fell from a church.

[10] Moreover, Ischia is a zone with a high number of irregular buildings, and many critics considered the poor construction materials as the main cause for the death of the two women and for the damage.

Significant acreage of land previously used for agriculture has been developed for the construction of houses or residential buildings.

Many houses and structures across the island sustained moderate to severe damage when the earthquake hit.