The country has reported more than 160,000 COVID-19 cases, according to the latest tally from Johns Hopkins University's Center for Systems Science and Engineering
The United States has tested 1 million people in its stepped-up effort to tackle the novel coronavirus, with a capacity to test 100,000 samples daily.
"Today we reached a historic milestone in our war against the coronavirus. Over 1 million Americans have been tested," President Donald Trump announced Monday at a White House briefing.
Alex Azar, US Secretary of Health and Human Services, said the United States is now testing 100,000 samples a day in their effort to combat the outbreak.
The country has reported more than 160,000 COVID-19 cases, according to the latest tally from Johns Hopkins University's Center for Systems Science and Engineering (CSSE).
As of 9:30pm Eastern Time on Monday (0130 GMT on Tuesday), there were 163,429 confirmed cases in the United States, with 3,008 deaths, an interactive map maintained by the CSSE showed.
Washington DC Mayor Muriel Bowser on Monday issued an order directing residents to stay at home unless there is an essential reason for going out, such as getting food and medical care, performing or accessing government services or engaging in essential business or travel.
It is a crime to disobey the order, and people who violate it could face up to 5,000 US dollars in fines, imprisonment for no more than 90 days, or both, said Bowser.
"Staying at home is the best way to flatten the curve and protect yourself, your family, and our entire community from COVID-19," said the mayor.
As of Monday, total confirmed COVID-19 cases in Washington reached 401, with nine deaths, according to the CSSE.
The District had earlier ordered all nonessential businesses to shutter, and the latest order came as similar measures were taken on the same day by the states of Maryland and Virginia.
New York City, where non-essential businesses are also closed till April 15 in accordance with a statewide mandate, has also tightened rules on social distancing, which experts say is essential to slowing the spread of COVID-19.
Local police have been patrolling on the street dispersing public gatherings over the past week. Mayor Bill de Blasio said on Sunday that those who do not practice social distancing will be fined between 250 and 500 US dollars by police.
On Monday, New York City greeted the US Navy Ship Comfort, which brought 1,000 hospital beds and 1,200 medical personnel to help relieve the city's overwhelmed hospital system amid COVID-19 pandemic.
The ship also contains 12 fully-equipped operating rooms, a medical laboratory, a pharmacy, an optometry lab, a CAT-scan, among other facilities, according to the website of the Navy.
It will start operating on Tuesday to treat non-COVID-19 patients so as to free up beds in local hospitals which can be focused on fighting the pandemic by establishing more intensive care units, officials have said.
The most populous city in the country has been the hardest hit with over 36,000 cases reported by Monday afternoon, data compiled by the CSSE showed.
"New Yorkers thank this nation for the help they're giving New Yorkers today, and we will reciprocate the favor. And what we're learning here, and the training that's going on here, is going to benefit the places all across this nation in the coming weeks and the coming months," said New York Governor Andrew Cuomo while welcoming the ship at Pier 90 in Manhattan.
Monday also marked the opening of the first 1,000 temporary beds in the field hospitals assembled by the Army in the Jacob K. Javits Center in Manhattan.
The governor said the hospitals will provide altogether 2,500 beds which are also for treating non-COVID-19 patients.
"So, we are doing this ship - 1,000 beds; Javits - 2,500 beds. About 3,500 beds to relieve the stress that our hospital system is facing," he added.