Italy instituted a mandatory quarantine for 16 million people in the northern part of the country that includes Milan and Venice, in a desperate bid to slow the spread of the coronavirus.

Under new regulations that were passed overnight people living in the Lombardy region — where Milan is the capital — and 11 nearby provinces must “absolutely avoid any movement into and out of the areas,” according to a draft decree from the Italian prime minister’s office seen by The Wall Street Journal.

The quarantine will last until April 3, according to the draft, and residents could face fines or jail time if they attempt to enter or leave the area before then (unless they obtain permission for a serious reason), The Guardian reported.

“We are facing an emergency,” Prime Minister Giuseppe Conte said in announcing the government decree at a news conference after 2 a.m. Sunday morning local time, The New York Times reported. “A national emergency.”

The new decree for the region also bans public events, conferences, and religious and civil ceremonies like weddings and funerals. Cinemas, theaters, gyms, bars, ski resorts and museums will be shut down. Schools and universities have already been closed, and that will continue.

People will be instructed to move about only for emergencies and work obligations that absolutely can’t be postponed.

In Italy, which is facing Europe’s largest coronavirus outbreak, nearly 6,000 people have been infected with COVID-19, the disease caused by the virus, and 233 have died from it. The country has documented the largest number of infections outside Asia, which jumped by nearly 1,200 in a single 24-hour period ending Saturday.

The outbreak in Italy began two weeks ago and the northern regions of Lombardy, Emilia-Romagna and Veneto have so far suffered 85% of cases and 92% of the deaths.

Close to 50,000 Italians were already affected by some quarantine measures. The dramatic new restrictive quarantine will involve a quarter of Italy’s population and would be the most radical action to deal with COVID-19 since China quarantined some 500 million people earlier this year, which has appeared to significantly slow the spread of the disease there.

“We will win this battle if our citizens adopt a responsible attitude and change their way of living,” Angelo Borrelli, the head of Italy’s civil protection agency, said at a press conference on Saturday.