American Airlines was forced to ground all flights in the US on Christmas Eve due to an unspecified technical issue.
The airline did not immediately say why it was stopping all flights, but social media was quickly abuzz with travellers worrying about getting to their loved ones for the holiday.
A groundstop notice was lifted not long after it was issued, but the possibility of disruption remains with so many flights needing to make up time.
Earlier on Tuesday, the airline said on social media: “An estimated timeframe has not been provided, but they’re trying to fix it in the shortest possible time.”
The Federal Aviation Agency said American Airlines was reporting “a technical issue and has requested a nationwide ground stop”.
In an update on Tuesday afternoon it said: “American Airlines reported a technical issue this morning and requested a nationwide ground stop. The ground stop has now been lifted.”
Passengers on social media reported having their flights stuck on the runway at various airports and being sent back to the gate.
American Airlines operates thousands of flights per day to more than 350 destinations in more than 60 countries.
Donald Trump says that when he takes power next month he will direct the US Justice Department to “vigorously pursue” the death penalty.
The US president-elect, 78, said he would do so to protect Americans from what he called “violent rapists, murderers and monsters”.
Mr Trump was responding to President Joe Biden’s decision to commute the sentences of almost all federal inmates on death row – whom Mr Trump called “37 of the worst killers in our country”.
“When you hear the acts of each, you won’t believe that he did this. Makes no sense,” Mr Trump posted on his social media platform Truth Social.
“Relatives and friends are further devastated. They can’t believe this is happening!”
He continued: “As soon as I am inaugurated, I will direct the Justice Department to vigorously pursue the death penalty to protect American families and children from violent rapists, murderers, and monsters.
“We will be a Nation of Law and Order again!”
President Biden, 82, announced on Monday that he would reduce the sentences of 37 of the 40 federal death row prisoners to life in prison without the possibility of parole, saying he was “guided by my conscience and my experience as a public defender”.
The three others the president did not spare are Robert Bowers, who fatally shot 11 people at a Pittsburgh synagogue in 2018; Dylann Roof, who gunned down nine black churchgoers in Charleston, South Carolina, in 2015; and Dzhokhar Tsarnaev, who carried out a 2013 bombing at the Boston Marathon that killed three people and injured almost 300 others.
‘I condemn these murderers’
Despite sparing the lives of 37, Mr Biden added: “Make no mistake: I condemn these murderers, grieve for the victims of their despicable acts, and ache for all the families who have suffered unimaginable and irreparable loss.”
During Mr Trump’s first term in office between 2017 and 2021, the US Justice Department put 13 federal inmates to death.
He has since said he would like to expand capital punishment to include child rapists, migrants who kill US citizens and law enforcement officers, and those convicted of drug and human trafficking.
Mr Biden, who ran for president opposing the death penalty, put federal executions on hold when he took office in January 2021.
His latest decisions come after a coalition of criminal justice advocacy groups, former prosecutors and business leaders wrote letters to the White House asking for Mr Biden to commute the sentences ahead of Mr Trump’s inauguration on 20 January.
Pope Francis also appealed to Mr Biden, who is Catholic, to reduce the sentences to imprisonment.
Unlike executive orders, clemency decisions cannot be reversed by a president’s successor, although the death penalty can be sought more aggressively in future cases.
Denmark has announced plans to boost its defence spending for Greenland with a “stronger presence in the Arctic” – a few hours after Donald Trump repeated his call for the US to buy the vast island.
Danish defence minister Troels Lund Poulsen said the package would amount to a “double-digit billion amount” in krone, or at least $1.5bn (£1.2bn).
He told the Jyllands-Posten newspaper the money would be used to buy two inspection ships, two long-range drones and two sled dog teams as well as more personnel for Denmark’s Arctic Command in the capital Nuuk.
Denmark will also upgrade the Kangerlussuaq Airport so that it can handle F-35 fighter jets.
Greenland, which sits between the Atlantic and Arctic oceans, is 80% covered by an ice sheet and is home to a large US military base.
The world’s biggest island, whose capital is closer to New York than the Danish capital Copenhagen, has mineral, oil and natural gas wealth.
But development has been slow, leaving its economy reliant on fishing and annual subsidies from Denmark.
“For many years, we have not invested sufficiently in the Arctic, now we are planning a stronger presence,” Mr Poulsen said.
He called the timing of the announcement an “irony of fate”, coming just hours after Mr Trump’s latest comments on purchasing the territory.
With the Pituffik air base, Greenland is strategically important for the US military and its ballistic missile early-warning system.
Greenland defiant
The president-elect sparked anger on the territory when he wrote that American ownership and control of the island was an “absolute necessity” for “purposes of national security and freedom throughout the world”.
Its prime minister Mute Egede hit back, saying: “Greenland is ours. We are not for sale and will never be for sale. We must not lose our long struggle for freedom.”
And Danish defence minister Mr Poulsen said: “My response to Trump is the same as the prime minister’s. Greenland does not want to exchange the Commonwealth for other relations. But that is up to Greenland itself.”
Mr Trump also proposed buying Greenland during his first term in office – an idea the Danish Prime Minister Mette Frederiksen called “absurd”.
Greenland has been part of Denmark for more than 600 years and gained autonomy from the country in 1979.
Under Greenland’s self-government act, enacted by Denmark and Greenland in 2009, Greenlanders are recognised as a people or nation entitled to the right of self-determination, with the option of independence.
On Monday, in an announcement naming Ken Howery as his ambassador to Denmark, Mr Trump wrote: “For purposes of national security and freedom throughout the World, the United States of America feels that the ownership and control of Greenland is an absolute necessity.”
He has also threatened to take back control of the Panama Canal, accusing Panama of charging excessive rates to use the waterway, which allows ships to cross between the Pacific and Atlantic oceans.
Former US president Bill Clinton is in hospital in Washington DC after developing a fever.
Mr Clinton, 78, has been admitted to MedStar Georgetown University Hospital for “testing and observation”.
Angel Ureña, the 42nd president’s deputy chief of staff, told Sky’s US partner network NBC News he is in “good spirits and grateful for the care he is receiving”.
Another source close to Mr Clinton said the situation is “not urgent”.
“The former president will be fine,” the source added. “He developed a fever and wanted to be checked out. He is awake and alert.”
Mr Clinton was active on the campaign trail in support of vice president Kamala Harris this year and has also been promoting his book Citizen.
The former president, who served two terms from January 1993 until January 2001, also addressed the Democratic National Convention in Chicago this summer.
Since leaving office, Mr Clinton has undergone two heart operations in New York – having a quadruple bypass operation in 2004, and two stents inserted into a coronary artery in 2010.
He was also in hospital for six days in 2021 with a urological infection that spread to his bloodstream.