UPDATE: May 28, 2017 – 3:19PM

British Airways has said it is resuming some flights from London today after a global IT malfunction necessitated the cancellation of what is reported to be hundreds of flights from Heathrow and Gatwick airports yesterday.

The malfunction affected check-in systems, baggage systems and all operational systems according to British Airways CEO Alex Cruz, and all inbound and outbound flights into the two London airports were cancelled, affecting thousands of passengers around the world.

Today, on a video posted to all British Airways social media sites, Cruz told customers, “Many of our IT systems are back up today and my colleagues across the airline are working very hard to build back our flight program and get as many of our customers as possible away on their travels.

The airline has said it has a “near-full” operation at Gatwick, although some delays are expected as the airline continues to deal with the aftermath of yesterday’s cancellations.

Cruz also said the airline plans to operate all long-haul flights from Heathrow today, although the “knock-on” effect from yesterday will lead to delays. Additionally, the airline has cancelled some short-haul flights.

The Financial Times, however, is reporting that nearly a third of British Airways flights have been cancelled today as well.

Inside and out at British' Airways' Terminal 5, thousands of passengers are standing in long lines as they hope to check-in for today’s flights or get re-booked after being denied boarding yesterday. Heathrow International Airport and British Airways are confirming that passengers are not even allowed to enter Terminal 5 unless they have a confirmed booking for a flight departing within a 90-minute window.

Further, they are asking passengers not to arrive early and not to come to the airport unless they have a confirmed booking for today.

Because the computer malfunction affected baggage systems, many passengers were forced to leave the airport last night without their bags. Today, the airline has started returning bags to passengers by courier service. But this is leading to fears of further inconvenience, as passengers worry they might depart for their travels just as their bags are being delivered back to their home address.

For some affected passengers, British Airways also promised to refund costs for overnight stays, ground transportation, but it will only make those determinations on a “case by case” basis. Additionally, the airline has asked passengers to pay for those costs and submit a claim for a refund, rather than providing vouchers up front.

Coby Benson, Flight Delay Legal Manager with U.K.-based solicitors, Bott & Co, has said that passengers affected by the malfunction are well within their rights to expect reimbursements for their expenses.

"The specific criteria for amounts and delay lengths depend on whether alternate flights were offered or not and how long the delay ultimately lasted for,” said Bott. “BA can’t get away with refunding passengers and hoping that’s the end of the matter – they are obliged to provide compensation under Regulation 261/2004 and we’re preparing for a busy week helping passengers recover that compensation.”

Still, many passengers were unable to secure accommodations as many airport area hotels were sold out. Others properties dramatically inflated their overnight rates, with charges for a standard hotel room running as high as £2,500 last night, according to The Telegraph.

Stranded passengers furious as #BritishAirways apologises for IT chaos pic.twitter.com/QImtZqwuhw

— The Telegraph (@Telegraph) May 28, 2017

British Airways has also said affected passengers can receive a full refund if they choose not to fly. Or they can rebook their flight, at no additional costs, for flights through November.

In a statement on its website, Heathrow Airport has said it is “continuing to provide additional customer service colleagues in the terminals to assist passengers affected. We are also continuing to give passengers free water and snacks.”

In his video speech, Cruz has apologized to passengers. “I know this has been a horrible time for customers,” he said. “Some of you have missed holidays. Some of you have been stranded on aircraft. Some of you have been separated from your bags.”

“On behalf of everyone at British Airways I want to apologize for the fact that you’ve had to go through this very trying experiences and to thank you for your patience and your understanding.”

Original Story:

Travellers are experiencing mass chaos at two of the U.K.'s busiest airports as British Airways has cancelled all flights into and out of Heathrow and Gatwick airports today due to “an issue with a worldwide British Airways’ IT system.”

As of press time, British Airways cancelled all inbound and outbound flights to the two airports as of midnight local time Saturday. But the airline has already pushed the deadline once--they originally announced the cancelations would last until 6 p.m. The airline has indicated it has no idea how long it will take to fix the situation. 

The cancellations come at the beginning of a busy bank holiday in my global destinations, including the U.K> and are causing traveller headaches at many the world’s busiest international airports.

Although British Airways assures passengers that there’s no evidence of a cyber attack, at least one British publication, the Daily Mail, has reported that customers heard a captain and gate crew tell passengers that the airline could be under cyber attack.

Instead, British Airways says the issue is due to a “system failure.”

According to an article at India news portal, The Quint, the British General Trade Union has blamed the system failure on British Airways’ decision to outsource its IT operation to India in 2016, a sentiment which is being echoed by a number of Twitter users as well.

British Airways will regret outsourcing IT to India. I bet costs today alone would have funded their old IT system here for years. #owngoal

— Kieran_1981 (@Kieran_1981) May 27, 2017

Whatever the cause of the failure, the issue has kicked off a day of turmoil for passengers attempting to travel into and out of the U.K. this weekend.

While the airline originally said it was canceling all flights from Heathrow and Gatwick until 6 p.m. local time, its pushing back of that deadline has caused further turmoil as more passengers have now headed to an airport already clogged with frustrated, angry passengers.

According to some reports, passengers are being asked to wait in long check-in lines only to ultimately be turned away because agents couldn’t retrieve their records. Because airline personnel can’t retrieve passenger info, they are also unable to rebook passengers onto other flights.

Others are reporting that is taking up to three hours just to leave the airport. Because the baggage system has also been affected by the outage, people are also unable to take their checked luggage with them when they leave the airport.

Absolute chaos at #Heathrow @British_Airways systems are down, people freaked out bags are piled up! What a #travel #nightmare pic.twitter.com/9mFVc6dd27

— Anna Anisin (@AnnaOnTheWeb) May 27, 2017

This is less than half way in the queue to get out of #Heathrow great work #britishairways! pic.twitter.com/WrnFTwoGiB

— MPC (@mpc1133) May 27, 2017

The outage has affected parts of the British Airways main website, its airline app and even some of the in-airport information systems, causing staff to write airline updates on a whiteboard to keep the public informed.

The airline has said affected passengers will be eligible for refunds on such expenses such as hotels, ground transportation and meals, but is distributing a letter asking customers to pay now and make a claim later. In a case of ultimate irony, the airline is sending customers to the airline website to make their claims.

BA official position on refunds for cancellations and delays today. Please retweet to those outside the airport @British_Airways #BA pic.twitter.com/APbDGeehK4

— Luke Hallard (@fLukeozade) May 27, 2017

Some passengers have reported being stuck on a plane for hours before being allowed to deplane into the airport.

Whether true or not, British Airways, which recently did away with free meals, has reportedly been selling food and coffee to passengers stuck on the tarmac as they wait for a gate.

@British_Airways Simply not good enough. Selling food to passengers on delayed flights stuck for hours on runways is beyond appalling #holdyourheadinshame

— David Lightman (@Mind_Poet) May 27, 2017

There is no word as to when British Airways will resume normal operations, but the airline has issued a statement that it is working as hard as it can to “resolve these issues.”

British Airways is asking passengers to avoid London’s airports today and to check with the airline website before heading to the airport on Sunday.

More passenger reactions:

Yesterday vs today in the life of @British_Airways pic.twitter.com/AUaSLd4joS

— Plane Finder (@planefinder) May 27, 2017

UPDATE 2 | All @British_Airways flights leaving from @HeathrowAirport this evening (UTC+1) have been cancelled after a BA IT issue. pic.twitter.com/XzQQaygYtW

— Heathrow Airport (@HeathrowAirport) May 27, 2017

Breaking: British Airways is rehearsing before cliff-edge Brexit when government walks out from the talks.

— Self Vertroue EU (@Selfvertroue91) May 27, 2017

#Naples airport - no #BritishAirways staff in sight as 100s of stranded passengers wait for more than 1.5 hours for assistance pic.twitter.com/kFoOA2hvbj

— Sue Teodoro (@SueTeodoro) May 27, 2017

Um... This is fun. Thanks @British_Airways for the chaos. Goodluck to everyone #Heathrow #britishairwaysdelay pic.twitter.com/b21ZWQdpbv

— Toby Ingham Thomas (@toby_it) May 27, 2017

Devastated. Flew from NY to run the Edinburgh Marathon and BA has cancelled all flights and won't give me my bags @British_Airways #Heathrow

— Wild Way Round (@wildwayround) May 27, 2017

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