Key points:
- A cyber attack is causing disruption at several European airports
- Brussels Airport said it was "too early to say" when the issue would be fixed
- Heathrow Airport warned of a "technical issue" delaying passengers
- Live reporting by Michael Drummond
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One airport hit hardest - as 'worrying signs' following cyber attack
Travel expert Simon Calder tells our presenter Samantha Washington that there have been some worrying signs after a cyber attack caused disruption at European airports today.
He also explained which airport was hit hardest.
Watch the latest here...
Latest statement from Heathrow Airport
It's been a while since we had an updated statement from Heathrow Airport, which does appear to be experiencing delays and disruption this morning.
This was what they said at 8.31am:
"Collins Aerospace, which provides check-in and boarding systems for several airlines across multiple airports globally, is experiencing a technical issue that may cause delays for departing passengers.
" While the provider works to resolve the problem quickly, we advise passengers to check their flight status with their airline before travelling.
"Please arrive no earlier than three hours before a long-haul flight or two hours before a domestic flight. Additional colleagues are available in check-in areas to assist and help minimise disruption. We apologise for any inconvenience."
'The queues are terrible'
Maria Casey arrived at Heathrow Airport this morning for her Etihad Airways flight to Thailand, but had to wait three hours to drop her luggage off at Terminal 4.
"The queues are terrible," she told Sky News. "It was an absolute skeleton staff. Out of six of the desks there were probably two people".
Her flight has been delayed, she added.
"When we were queuing, because nobody was actually informing of us anything. So we were queuing for three hours and literally snaking and shuffling with this skeleton staff on the desk, and nobody was telling us then (what was happening)".
"But then I saw the breaking news on Sky News and I was like 'ah ok, cyber attack'."
It was taking 5-10 minutes to check in each person, Maria adds, because everything had to be done manually.
'No solution yet' to cyber attack, Brussels Airport says
Ariane Goossens, a spokesperson for Brussels Airport, says the disruption is indeed due to a cyber attack.
"So what's happening is that one of our external service providers, who provides us with a system for passenger check-in and boarding, was hit by a cyber attack last night.
"This is impacting processors, gates, and other European airports. What we're seeing is that as of this morning, there hasn't been a solution yet.
"So, very concretely, this means that passenger boarding and check-in is being done manually. This takes longer, which is why some flights are being cancelled or delayed."
Watch: 'Planes will still be taking off, but it's going to be slow'
Here's the latest and what you need to know on the cyber attack that's sparked havoc across major European airports from our presenter Samantha Washington and correspondent Rachael Venables...
Lines at Heathrow as airport warns of delays
We've received this picture from a viewer showing lines at Heathrow Airport.
The extent of any disruption at Europe's busiest airport remains unclear, as information about the cyber attack remains limited.
Collins Aerospace 'actively working to resolve the issue'
RTX, the owner of Collins Aerospace, one of the largest suppliers to the aviation industry in the world, said it is aware of cyber-related disruption to its software.
"We are actively working to resolve the issue and restore full functionality to our customers as quickly as possible," RTX said.
"The impact is limited to electronic customer check-in and baggage drop and can be mitigated with manual check-in operations."
The company said the issue with its MUSE software was identified after
major European flight hubs flagged delays due to a cyber attack.
Collins Aerospace technology allows passengers to check themselves in, print boarding passes and bag tags, and dispatch their own luggage, all from a kiosk.
What did the cyber attack target?
Details of the cyber attack are still emerging, but some information has been released by affected airports.
Authorities at Berlin’s Brandenburg Airport said a service provider for passenger handling systems was attacked on Friday evening, prompting airport operators to cut off connections to the systems.
London's Heathrow Airport said a "technical issue" affected a service provider for check-in and boarding systems.
It named Collins Aerospace as the company experiencing the issue, saying it may cause delays for departing passengers.
Collins Aerospace works with several airlines across multiple airports globally, Heathrow said.
Several major European airports experiencing disruption
Airports in Brussels, Berlin and London (Heathrow) are experiencing disruption following the cyber attack.
"It is still too early to say when the problem will be resolved," Brussels Airport said in a statement.
So far 10 flights have been cancelled at the Belgian airport and 17 were experiencing delays of more than an hour.