Huge crowds of people built up at Heathrow Airport this morning amid an apparent mass shortage of staff at security.
Dozens of members of the airport's departure team are off sick in Terminal Five, frustrated passengers on the ground have been told.
The whittled-down workforce has been struggling to process thousands of outbound passengers heading through the security gates.
People stuck in the airport said that some had missed their flights because of the wait.
The staffing issues, which come the rainy morning after more than 30 million tuned in to watch England lose to Italy in the Euro 2020 final, are said to be partly to do with Test and Trace.
Have you been caught up in the queues? Email webnews@mirror.co.uk
One Heathrow employee told a man stuck in the queue that the coronavirus tracking app had forced large numbers of their colleagues to isolate.
"Covid marshals are not even questioning people with masks under their chins," one delayed passenger told The Mirror.
"It is because of a shortage at security and also seemingly the NHS app has activated on a lot of staff, a member of staff told me."
Some of those at the airport have said staff "failed to turn up" because of the football.
One BA employee told The Telegraph: "I went to bed at 12 last night after the game then got up at 2.30 to do my job. Why can’t the security guards?"
People stuck in the queue took to Twitter to express their frustrations at the huge waits.
"It’s a disgrace. It’s like the line with no end,” said David Bennett, who was waiting with his three children to board a flight to Corfu.
“It must be because of the football last night.”
One man tweeted: "Four hour queuing for security, without any social distancing and everyone packed.
"Will you be responsible for the next clusters in UK?"
Another passenger estimated that there were 1,000 people waiting to get through security.
"I don’t think it’s an exaggeration to say there are more than a thousand people in the queue for security at Heathrow Airport right now," he said.
"And the Fast Track line, which I’m eligible for, is closed.
"This is a Newark-like experience at what’s supposed to be a world-class airport."
Another added: "How can you not have enough staff on as we’re being told that it’s staff shortages causing the issue at security control in T5?? You do know it’s July??"
Today is not the first time that passengers have been stuck in huge queues at Heathrow.
Mr Paul, 39, who preferred not to give his first name, flew from India, which is on the UK’s ‘red list’, to Heathrow Airport on June 28.
The IT consultant from South London, who is originally from India, was forced to wait hours in packed queues before his ten-day isolation, according to My London.
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Despite arriving at the airport at around 7.45am he only reached his quarantine hotel in Gatwick after 4.30pm.
Mr Paul, who had been in India since September with his wife, said there were almost 1,000 people in the immigration hall.
Waits have become longer during the pandemic in part due to additional paperwork that is required to enter and exit countries.
A Heathrow spokesperson said: “We're currently experiencing some passenger congestion in Terminal 5 departures.
"Our teams are working hard to get passengers away on their journeys and we hope to have the congestion cleared as quickly as possible.
"Passengers are reminded that face coverings are mandatory inside the airport.”
They later added: "Earlier today we experienced some passenger congestion in Terminal 5 departures, due to colleagues being instructed to self-isolate by NHS Test and Trace.
"We have activated additional team members to assist passengers with their journeys and the operation has now returned to normal.
"We apologise to our passengers for any inconvenience caused.”
An earlier version of this story incorrectly mentioned the Border Force in the headline.
