At least 16 people, including a family of four trapped in their ground-floor flat, have died in Sardinia after torrential rains and a cyclone caused rivers to burst their banks.

The Italian prime minister, Enrico Letta, described the fatalities as a "national tragedy", and the government declared a state of emergency on the islandafter six months' worth of rain fell within 24 hours.

Letta told Italian radio: "At this point, the priority is saving lives and helping those who have been evacuated. Unfortunately, we're talking about a lot of people. The deaths have also risen to a terrible number."

The north-east of the island appears to be worst affected, with 13 of the deaths occurring in the Olbia-Tempio province, according to the regional branch of Italy's civil protection agency.



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Among them was an entire family, believed to be Brazilian, including a mother, father, and two children reportedly aged 16 and 20. The four were found drowned inside their ground-floor flat in the town of Arzachena, the Ansa news agency reported.

Also in the north-east, three people were reportedly killed when their car was swept away after the collapse of a bridge. Flood waters in some parts of the island were 3 metres (10ft) high.

Speaking on SkyTg24, Sardinia's governor, Ugo Cappellacci, said people were still missing.

"The situation is tragic," he said. "The hotels in Olbia are full of people who have had to escape but there are thousands who have damage to their homes."

Emergency workers were trying to reach parts of the island that were hit overnight by the downpours and fierce winds of cyclone Cleopatra.

Italy's national civil protection chief, Franco Gabrielli, said: "This is a natural calamity. In 24 hours, there was the same amount of rain as usually falls in six months."

The mayor of Olbia, Gianni Giovanelli, likened the "apocalyptic" storm to "a real water bomb of huge intensity".

Letta said €20m (£16.8m) had been assigned for disaster response measures after the declaration of a state of emergency.

"[The state of emergency] enables us to immediately be able to use rules for more rapid interventions and set aside an initial sum for the very first emergencies that occurred during the night," he said.