March 15 (UPI) — New York City Mayor Bill de Blasio ordered all schools, bars, restaurants and entertainment venues in the city to close this week as part of aggressive measures to clamp down on the spread of COVID-19 in the city.

During a press conference Sunday, de Blasio announced that schools will be closed starting Monday until at least April 20 but the closure could last until the end of the school year, affecting some 1.1 million students.

De Blasio told reporters he is “very, very concerned” about the spread of the coronavirus in the city, which has 329 cases of COVID-19 and five deaths caused by the virus.

Last week, de Blasio declared a state of emergency, but he said Sunday more drastic measures were now needed.

“This is a decision I have taken with no joy whatsoever with a lot of pain,” he said, adding that he never imagined “in a million years” of canceling school.

As a parent of former New York City school students, he said he understands the negative effects the move will have but it is necessary.

“We are dealing with a challenge and a crisis that we have never seen in our lifetimes and is only just begun,” he said. “So I regret to have to announce that as of tomorrow our public schools will be closed.”

Officials will attempt to open the 1,800 schools mid-April, but there are “a lot of unknowns and a lot of challenges” that may keep them shuttered for the remainder of the school year, he said.

On March 23, the city will begin remote learning with students requiring technology necessary to participate can pick up devices on Thursday and Friday, the mayor’s office said, adding Apple and T-Mobile “will ensure that in the coming weeks, 300,000 New York City public school students who don’t currently have an Internet-connected device will have one for their schoolwork.”

De Blasio also announced later Sunday in a statement that he will be signing an executive order on Monday forcing all nightclubs, movie theaters and concert venues to close while limiting restaurants, bars and cafes to food take-out and delivery services.

“This is not a decision I make lightly,” de Blasio said in the statement. “These places are part of the heart and soul of our city. They are part of what it means to be a New Yorker. But our city is facing an unprecedented threat, and we must respond with a wartime mentality.”

Also on Sunday, Gov. Phil Murphy of New Jersey — which has 98 positive cases of COVID-19 and two deaths — said an extended statewide school shutdown was “imminent” with plans to announce specifics on Monday.

In Connecticut, Gov. Ned Lamont announced school closures via Twitter on Sunday, stating classes will be canceled until at least March 31 starting Tuesday. He also said he will update a previously declared state of emergency to limit gatherings to no more than 50 people as recommended late Sunday by the U.S. Centers for Disease Control and Prevention.

Several states and cities have already adopted drastic measures to combat the spread of COVID-19, including Illinois and Ohio who separately announced earlier Sunday that they would close all bars and restaurants. California also said it was ordering those over 65 years of age to isolate themselves at home isolation.

Last week, Maryland, Ohio, Michigan, New Mexico, Oregon and the District of Columbia also ordered their schools closed amid the COVID-19 epidemic.