The order is indefinite. All residents must stay at home, and no employees can go to work anymore unless they are in the essential categories. All gatherings of any size are also canceled.
New Jersey joins New York and California in issuing similar restrictions.
The governor announced Saturday that there had been five more deaths from the virus, for a total of 16 in the state. There were more than 440 new positive tests for a total of more than 1,300, something he attributed to testing in the state that had been "ahead of the curve."
He ordered all residents to stay at home with some exceptions, such as obtaining essential goods or services, seeking medical attention, visiting family or close friends, reporting to work, or engaging in outdoor activities. Gatherings such as weddings, in-person services and parties are banned, he said.
"It pains me that important life moments cannot be celebrated the way they are supposed to," Murphy said. "Any place where people congregate is a place where coronavirus can be spread."
Murphy also urged people not to go to second homes at the Jersey Shore, saying the shore towns aren't prepared for the influx. All businesses were told to move their employees to work from home wherever possible.
Asked how long he expected the restrictions to last, Murphy said he guessed it would be "somewhere measured in weeks to months."
"Life in New Jersey does not have to come to a complete standstill," Murphy said. "Residents can still go for a walk or go for a run outside. ... If you do go outside for these activities, or head to the grocery store, we're urging ... no, we're ordering everyone to practice social distancing and keep a safe, six-foot difference between you and others."
Murphy earlier announced the indefinite closure of libraries across the state.
The state lists essential employees as including but not limited to: law enforcement officers, firefighters, other first responders, cashiers or store clerks, construction workers, utility workers, repair workers, warehouse workers, lab researchers, IT maintenance workers, janitorial and custodial staff, and certain administrative staff.
The state announced a new website, https://covid19.nj.gov/, that features information on the fight against COVID-19.
Here is a full list of essential services that can stay open.
Grocery stores, farmer's markets and farms that sell directly to customers, and other food stores, including retailers that offer a varied assortment of foods comparable to what exists at a grocery store
Pharmacies and medical marijuana dispensaries
Medical supply stores
Ancillary stores within healthcare facilities
Hardware and home improvement stores
Banks and other financial institutions
Laundromats and dry-cleaning services
Stores that principally sell supplies for children under five years
Car dealerships, but only for auto maintenance and repair, and auto mechanics
Printing and office supply shops
Mail and delivery stores.
The Associated Press contributed to this report.
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