A helicopter searches for missing passengers after a tourist boat capsized in a storm on Lake Maggiore, Italy, on Sunday.
CNN  — 

The bodies of four people have been recovered from Lake Maggiore in northern Italy after a tourist boat capsized on Sunday evening, Italy’s fire service has said.

Search and rescue operations have now concluded after the last body was recovered at 8 a.m. local time (2 a.m. ET), the fire service, Vigili del Fuoco, said in a tweet Monday.

The victims included two Italian nationals, one Israeli and one Russian, CNN affiliate Sky Tg24 reported Monday, citing the local prosecutor. The victims were two men and two women.

The 16-meter (52-foot) houseboat had been carrying 24 people when it encountered difficulty during a “violent storm” and capsized shortly after 7:30 p.m. local time (1:30 p.m. ET) on Sunday, Sky Tg24 reported.

There were 22 tourists on board, including British passengers, and two crew members, according to Sky Tg24.

A diver searches for bodies after  a rescue operation in Lake Maggiore, northern Italy.

Twenty people were rescued after the boat capsized, the fire and rescue service said.

Some of the 20 survivors reportedly managed to swim to the shore, according to Sky Tg24, adding that, although five were taken to the hospital, no survivors had sustained any serious injuries.

Divers and a helicopter were used as part of the search and rescue operation, according to the fire and rescue service.

Among those killed was the skipper of the boat’s girlfriend, while one of the bodies was found within the wreckage of the boat, roughly 15 meters (49 feet) below water, Sky Tg24 added.

An operation is now underway to recover the sunken boat.

A UK Foreign Commonwealth Development Office spokesperson told CNN, “we are in contact with local authorities in Italy after a boat accident and are ready to provide consular assistance to any British nationals involved.”

Lake Maggiore is a popular destination for tourists and is shared by Italy and Switzerland.

Passengers had been celebrating a birthday party when the boat, traveling between the Italian towns of Lisanza and Dormelletto, capsized, according to Sky Tg24.