iN VIDEO: California governor orders statewide stay-at-home order

SACRAMENTO, Calif. (AP) — California Gov. Gavin Newsom on Thursday ordered the state's 40 million residents to stay at home, restricting non-essential movements to control the spread of the coronavirus that threatens to overwhelm the state's medical system.

“This is a moment we need to make tough decisions,” Newsom said. "We need to recognize reality.”

His move came after counties and communities covering about half the state's population already had issued similar orders. He said the restriction is "open-ended," and it could raise false hopes if he predicted how long the order might last.

People may still leave their homes for walks and exercise and for essential needs such as food and medical care. Restaurant meals can still be delivered to homes.

The Democratic governor also announced that he is mobilizing 500 California National Guard troops to help with food distribution, but said they will be in place only for humanitarian reasons.

The move comes amid a day of dizzying developments as governors across the U.S. sounded a perilous alarm about the rapid spread of the new coronavirus and warned of dire consequences for their health care systems.

Pennsylvania's governor ordered more than 150 types of businesses to close, the governor of Texas closed schools for more than 5 million students and the Louisiana governor delivered a grim assessment of his state to President Donald Trump.

U.S. governors told the president Thursday that their states are in immediate need of federal help as they expand measures to contain the new coronavirus. Louisiana Gov. John Bel Edwards said his state's health system could be overwhelmed in a week.

"Our trajectory is basically the same as what they had in Italy. And if there’s anything I said today that ought to get people’s attention, it is that," the Democratic governor said. “If we are not going to look like Italy in 10 days or two weeks, it will only be because of these mitigation measures.”

In a conference call with other governors, Edwards warned Trump of the “worst-case scenario” modeling. But he also told reporters that Louisiana was on track for that “sobering” reality if the state's residents don't actively work to decrease contact with others — staying home more and distancing themselves from people.