Four people died when a boat carrying tourists overturned on Lake Maggiore in strong winds, Italy's fire brigade said Monday.
The boat tipped over Sunday off Lisanza, at the southern end of the lake in northern Italy, after the weather suddenly turned stormy.
"The bodies of four people have been recovered," fire brigade spokesman Luca Cari told AFP.
The president of the Lombardy region, Attilio Fontana, said Sunday a "whirlwind" had caused the 16-metre (52-foot) long boat to overturn.
Around 20 survivors were rescued by passing boats or swam to shore, Italian media said.
Lake Maggiore is the second largest lake in Italy and is a popular tourist site. File photo: AFPThe boat had been carrying both Italian and foreign tourists, and it sank quickly, taking one of the victims with it, according to reports.
A firefighters' video showed a search and rescue helicopter flying over choppy waters, where chairs and other debris could be seen floating.
Lake Maggiore, which lies on the south side of the Alps, is the second-largest lake in Italy and a popular tourist destination.