Questions remain over a boat that sank in Italy's Lake Maggiore, leading to four deaths.
Those killed were a former agent for an Israeli spy agency, two Italian intelligence officers and the fourth victim was a Russian woman.
The Italian victims were named as Tiziana Barnobi, 53, and Claudio Alonzi, 62, a delegate of Italy’s secret service confirmed, while a spokesperson for Israel’s foreign ministry identified the Israeli victim as Shimoni Erez, 60, according to CNN.
They were among 23 on board the 16-metre houseboat cruising the lake.
While initial reports said the ride was an innocent pleasure trip - several Italian news outlets now claim it was a secret work meeting between Italian and Israeli agents.
Only the captain, Claudio Carminati, and his Russian wife were not affiliated with the secret services.
Mr Carminati is under investigation for culpable manslaughter, according to the Italian prosecutor.
Two bodies had been recovered by firefighter divers on Sunday evening, while the fourth victim had died shortly after being rescued following the capsizing of the houseboat, which the owners used as a tour vessel to take visitors around Lake Maggiore, police said.
Some reportedly managed to swim to shore, or were picked up by other boats. The houseboat sank, police said.
The incident unfolded when the boat was hit suddenly by a fierce storm - with gusts of over 70km per hour.
The whirlwind was part of a storm system that hit the region of Lombardy on Sunday evening, forcing delays at Milan's Malpensa airport.
Mr Carminati told investigators that no bad weather had been forecast. He is now being investigated for the possible crimes of causing a shipwreck and culpable homicide.
Further adding to the mystery, Italian media report the survivors seemingly rushed to leave their hotel rooms and the hospital where they had received treatment immediately afterwards.
Passengers had been reportedly celebrating a birthday party when the boat, traveling between the Italian towns of Lisanza and Dormelletto, capsized, according to Sky Tg24.
There is no paperwork about those who received medical treatment.
A delegate of the Italian secret service issued a public condolence “sharing closeness and pain for the tragic event to the families of the victims.”
Italy’s military police, the Carabinieri, are assisting with the investigation, the prosecutor’s office told CNN.
Lake Maggiore is a popular destination for tourists and is shared by Italy and Switzerland.
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