A luxury superyacht carrying foreign tourists capsized and sank off Sicily in bad weather early Monday. One body was found, six people remain missing and 15 people were rescued, authorities said.

The ship had overturned around 5 a.m. off the port of Porticello, where it was apparently anchored. It had a crew of 10 people and 12 passengers, including British, American and Canadian nationalities, the Italian coast guard said. Local media said a sudden fierce storm, including tornados over water known as waterspouts, had battered the area overnight but skies were clear and seas calm by Monday morning.