The captor, who died in the 10-hour siege in the small town of Colleyville on Saturday, was named by the FBI as 44-year-old Malik Faisal Akram.

Some of the faithful had arrived in the area days in advance from as far away as Florida or Texas, waiting to hear him trot out a familiar list of grievances.

In contrast to what Human Rights Executive Director Kenneth Roth described as former US President Donald Trump's "embrace of friendly autocrats", Biden took office in January 2021 with a pledge to put human rights at the center of his foreign policy.

Seventy-six percent of those surveyed in the poll by Quinnipiac University said they think political instability in the United States is a bigger danger than foreign threats.

These included some executives and staff of major South Korean companies, according to industry sources and one company.

With temperatures up around 45°C (113°F) in parts of the South American nation, hundreds of thousands of people were left without electricity when power grids failed in and around populous capital city Buenos Aires.

The previous record was 1.03 million cases on Jan. 3. A large number of cases are reported each Monday due to many states not reporting over the weekend. The seven-day average for new cases has tripled in two weeks to over 700,000 new infections a day.

Prosecutors in Brooklyn say Thomas Welnicki "knowingly and willfully threatened to kill, kidnap, and inflict bodily harm upon" the former US president.

Harris, then the vice-president elect and senator from California, evacuated the Democratic National Committee (DNC) headquarters on Capitol Hill after law enforcement officers discovered the device, said the official, speaking on condition of anonymity.

Biden and his top aides have been reluctant to talk directly about Trump since he took office last January, even as the Republican former president continued to spread lies about his election loss.

The number of hospitalized COVID-19 patients has risen nearly 50 percent in the last week and now exceeds 100,000, according to data collected by Reuters, marking the first time that threshold has been reached in a year.

The White House said Biden would push back against Trump's false claims, adopted by many of his followers, that his election defeat was the result of widespread fraud, as well as attempts to downplay the violence of the worst assault on the Capitol since the War of 1812.

State Attorney General Letitia James, a Democrat, issued the subpoenas seeking their testimony in her years-long civil probe last month, according to the document.

The January 6 attack on the seat of Congress, led by supporters of Donald Trump, was "a harbinger of increasing political violence," and American democracy "is threatened," according to two-thirds of those surveyed for a CBS News poll.

The lawmaker from Georgia is a loud and fervent supporter of Donald Trump and his false claims that the 2020 election was stolen, and is also known for making outlandish anti-vaccine claims and other false statements about the coronavirus pandemic.

"I don't consider him the president of the United States," the retired US Air Force veteran told AFP at his New Hampshire home surrounded by oak and birch trees and houses displaying "TRUMP" signs.

News of Austin's positive test comes after the Pentagon last week tightened restrictions at its headquarters over concern about the highly transmissible Omicron variant that has led to a sharp increase in COVID-19 infections throughout the world.

Was it a simple protest-turned-riot? An insurrection? A coup attempt plotted by Trump? 

The United States had 2,604 cancelled flights, more than half of the 4,529 cancelled worldwide, shortly after 4:30 pm (2130 GMT), according to tracking website FlightAware. 

In a 50-minute call, their second conversation this month, Biden said he needed to see Russia decrease its military build-up near Ukraine, while Putin said sanctions threatened by Washington and allies could lead to a rupture in ties. The call was requested by Putin.

"I would imagine given the size of our country, and the diversity of vaccination versus not vaccination, that it's likely to be more than a couple of weeks, probably by the end of January," he said on CNBC.

Monday's travel woes marked a fourth day of flight cancellations, capping a glum Christmas weekend for thousands of passengers who were left waiting in airport queues and on customer service phone lines to re-book flights.

For the results of the gubernatorial races -- victory in leftward-trending Virginia and an unexpectedly narrow defeat in deeply Democratic New Jersey -- proved one thing beyond doubt: Republicans can win without Donald Trump.

It is estimated that airline carriers globally scrapped at least 2,366 flights on Friday, which fell on Christmas Eve and is typically a heavy day for air travel. Nearly 9,000 more flights were delayed.

"That would increase the prospect of running," Biden told ABC News on Wednesday.

An antigen test that Harris received Wednesday morning as part of regular testing and a PCR test after being notified of the staffer's case both came back negative, the White House said, quoted by Reuters.

In a televised address, Biden formally announced a raft of new measures to combat the winter surge -- including shipping half a billion at home tests -- but denied his administration had failed to adequately prepare for the fresh wave of cases.

The announcement came as the United States is seeing another surge in coronavirus cases, with Omicron accounting for about two-thirds of new infections last week, according to the latest data from the Centers for Disease Control and Prevention.

"The rapid spread of the Omicron variant reinforces that we must all continue to accelerate our efforts to end this pandemic and that none of us are safe until all of us are safe," Blinken said in a statement.

A PCR test Biden received on Monday after being notified of the case came back negative, as did an antigen test he received on Sunday as part of his regular testing, White House spokesperson Jen Psaki said in a statement.