A landslide engulfed buildings during heavy rain on the southern Italian holiday island of Ischia on Saturday.
A wave of mud swept down a hill in the small town of Casamicciola Terme in the early morning, engulfing at least one house and sweeping cars down to the sea, media reports and emergency services said.
There has been confusion over how many people have been killed. Interior Minister Matteo Piantedosi said no deaths had been confirmed but Infrastructure Minister Matteo Salvini said that eight people had died in the slide.
The fire brigade said searches were under way for 13 people initially reported missing.
Among them was a family comprising a husband, a wife and a newborn baby who lived near where the landslide began, according to the Ansa agency.
The fire service said one house had been overwhelmed by the mud and that two people had been rescued from a car swept into the sea.
It said aid was being sent from Naples, the nearest major city, but weather conditions were making it difficult for help to reach the island.
"The search for the missing, evacuations and help for people in danger continues," the Department for Civil Protection said in an update on Twitter.
"The rescue effort remains complex due to the weather conditions."
Local authorities have called on residents of Ischia to stay inside so as not to hinder the rescue operation.
Prime Minister Giorgia Meloni is closely following the situation and offered her thoughts to those affected, her office said.
Ischia is a volcanic island around 30km (19 miles) from Naples that draws visitors to its thermal baths and picturesque coastline.
It is densely populated and has a large number of illegally built houses, putting inhabitants at permanent risk from flooding and earthquakes.
In 2006, a landslide killed a father and his three daughters on the island.