The number of people to have died from the coronavirus in Italy has shot up by 133 in a day to 366, officials say.
The total number of infections leapt 25% to 7,375 from 5,883, according to the Civil Protection agency.
The jump in figures comes as millions adapt to radical measures introduced on Sunday in an attempt to contain the outbreak.
Up to 16 million people in Lombardy and 14 provinces need special permission to travel under new quarantine rules.
Prime Minister Giuseppe Conte also announced the closure of schools, gyms, museums, nightclubs and other venues across the whole country.
The restrictions will last until 3 April.
The latest figures mean Italy now has the highest number of confirmed infections outside China, where the outbreak originated in December. It has overtaken South Korea, where the total number of cases is 7,313.
Among the latest people to test positive in Italy is the army's chief of staff. Salvatore Farina said he felt well and was self-isolating.
The strict new quarantine measures affect a quarter of the Italian population and centre on the rich northern part of the country that powers its economy.
The health system is under immense strain in Lombardy, a northern region of 10 million people, where people are being treated in hospital corridors.
"We want to guarantee the health of our citizens. We understand that these measures will impose sacrifices, sometimes small and sometimes very big," Prime Minister Conte said as he announced the measures in the middle of Saturday night.
Under the new measures, people are not supposed to be able to enter or leave Lombardy, where Milan is the main city.
The same restrictions apply to 14 provinces: Modena, Parma, Piacenza, Reggio Emilia, Rimini, Pesaro and Urbino, Alessandria, Asti, Novara, Verbano Cusio Ossola, Vercelli, Padua, Treviso and Venice.
Some transport in and out of the regions affected continued on Sunday. Flights still arrived at Milan's Malpensa and Linate airports, though some scheduled flights were cancelled.
However, Italy's national carrier Alitalia said it would suspend all operations from Malpensa from Monday and Linate would only serve domestic routes. International flights would continue to and from Rome.
The World Health Organization (WHO) chief Tedros Adhanom Ghebreyesus praised Italy for making "genuine sacrifices" with the restrictions. Until Sunday only about 50,000 people in northern Italy had been affected by quarantines.
Last week the government announced the closure of all schools and universities across the country for 10 days.
The government & the people of are taking bold, courageous steps aimed at slowing the spread of the #coronavirus & protecting their country & . They are making genuine sacrifices. @WHO stands in solidarity with & is here to continue supporting you.https://t.co/Y2rkgUihtA
— Tedros Adhanom Ghebreyesus (@DrTedros) March 8, 2020
End of Twitter post by @DrTedros
What is the situation elsewhere?
The number of infections worldwide is more than 107,000, with about 3,600 deaths.
Most of the fatalities have been in China. But the country on Sunday reported its lowest number of new infections in a single day since January – an indication that the virus's spread there is slowing.
Iran, one of the worst hotspots outside China, has now confirmed 6,566 infections and 194 deaths.
However, the real figure is feared to be much higher. One report on Sunday, quoting a government envoy, said there had been 200 deaths in the northern Gilan province alone – but the figures were later removed.
In other developments: