At least three people, including a young girl, were killed on the southern Italian holiday island of Ischia after a landslide caused by torrential rain devastated a small town, the office of the prefect of Naples said on Sunday.

Emergency workers stepped up search efforts a day after a landslide caused by torrential rain devastated Casamicciola Terme.

Some 10 people were still missing, according to data provided by the prefect earlier on Sunday.

Dozen of emergency officials have rushed to flood-stricken island.

On Sunday, rescue divers joined the efforts, searching the waters off the port of Casamicciola, where a wave of mud, debris and stones broke away from the island's highest mountain on Saturday and crashed down over houses and roads.

The island received 126 millimeters (nearly five inches) of rain in six hours, the heaviest rainfall in 20 years, according to officials. Experts said the disaster was exacerbated by building in areas of high risk on the mountainous island.

“There is territory that cannot be occupied. You cannot change the use of a zone where there is water. The course of the water created this disaster," geologist Riccardo Caniparoli told RAI. “There are norms and laws that were not respected.”