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An Italian doctor treating patients at the center of the worst coronavirus outbreak in Europe has issued a stark warning to other countries yet to be hit by the full force of the pandemic: lock down.

"We know what happens," Dr. Emanuela Catenacci told British broadcaster Sky News as she took a break from treating patients in an intensive care ward in Cremona Hospital in Lombardy. "Don't think it is happening here and it can't happen everywhere else ... because it will."

The death toll in Italy jumped by 793 to 4,825 on Saturday, by far the largest daily rise in absolute terms since the contagion emerged in the country a month ago. Last week, the number of those killed in Italy's outbreak surpassed those who died in China, where the disease emerged late last year.

"It is genuinely heartbreaking covering this story and it's made worse knowing that our own families are vulnerable too."



Chief correspondent @ramsaysky reports from an ICU in Italy on the "brink of collapse" during the #coronavirus pandemic https://t.co/RIC8yCHrc5 — Sky News (@SkyNews) March 22, 2020

While Lombardy, the center of the Italian outbreak, has been under lockdown for weeks, the central government has been criticized for not having acted quickly or forcefully enough to stem the outbreak. On Saturday, Prime Minister Giuseppe Conte described the crisis as the worst the country has faced since the end of World War II.

In the hospital in Cremona, east of Milan, Dr. Leonor Tamayo told Sky News, which, like NBC News, is owned by Comcast Corp., that the staff was being overwhelmed by a "tsunami" of patients.

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The hospital has run out of space to store bodies and has been forced to keep them in a nearby church.

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Comparing the outbreak to a "war," she said: "We are here 12 hours a day. Only, we are going home for a few hours and come back here for the work, because we are here for the patients."

As they struggled to cope with a huge number of patients, doctors said they are trying to dispel the myth that only the elderly are dying from coronavirus-related illnesses.

"Fifty percent of our patients in the intensive care unit, which are the most severe patients, are over 65 years old," Dr. Antonio Pensenti, the head of the intensive care crisis unit in the northern region of Lombardy, said Saturday. "But that means that the other 50 percent of our patients are younger than 65."

Pensenti said his team was treating "quite a few" patients ages 20 to 30, who were in a "severe" condition like the older patients, although he added that the younger patients were "usually healthier and survived more."

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Taking further restrictive measures to stem the outbreak, Attilio Fontana, governor of Italy's Lombardy region, signed a new order Saturday imposing even more stringent restrictions on residents, banning outdoor exercise and implementing temperature checks at supermarkets and pharmacies.

Pharmacies, supermarkets, banks and public transport will continue to operate.

After the announcement, national Finance Minister Roberto Gualtieri wrote on his social media accounts that it was "a necessary decision" that could "save human lives."

On Sunday, the Russian military will start sending medical assistance to help Italy battle the coronavirus after receiving an order from President Vladimir Putin, Russia's Defense Ministry said in a statement, according to Reuters.

Putin spoke to Conte on Saturday, the Kremlin said in a statement, adding that Putin had offered his support and help in the form of mobile disinfection vehicles and specialists to aid the worst-hit Italian regions.