While the CrowdStrike breakdown that left airport gate agents around the world with the “blue screen of death” back in July was eventually put under control, another airport is now dealing with a massive tech outage. 

This time, the massive outage affecting computers and phone systems at Seattle-Tacoma International Airport (SEA) is widely believed to be a cyberattack rather than a simple technology glitch.

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While the first outages began on Aug. 24, flights were still being delayed as of early Tuesday morning as airport officials continue to investigate the cause of the breakdown.

‘Get necessary systems back online and mitigate impacts to passengers’

“We’re working around the clock to get necessary systems back online and to mitigate impacts to our passengers,” SeaTac’s Aviation Management Director Lance Lyttle said in a press conference on Aug. 25.

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Airport officials further said that the attack affected “isolated critical systems” that include flight information displays throughout the airport and the systems tracking baggage dispensers.

Delta Air Lines  (DAL) and Alaska Airlines  (ALK)  have not reported any major delays and cancelations while smaller airlines using shared gates have had to manually write tickets to passengers and in some cases cancel flights.

Some of the most affected airlines include Frontier  (FRON) , Spirit  (SAVE)  and WestJet. FlightAware data shows that 177 delays and seven cancelations were recorded on Aug. 26 and at least 10 delays were recorded in the early hours of Aug. 28.

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‘Nefarious characters that may have been on our system’

The SeaTac website continues to be down as of Monday morning but the biggest damage has been done to the baggage sorting system — an Alaska Airlines spokesperson told local Seattle Times that its staff had to manually sort through more than 7,000 bags over the weekend in order to get them to the right carousel at the airport. 

As of Tuesday morning, the investigation being conduced in conjunction with airport authorities, the TSA and FBI has not led to any information to be announced to the public about the source of the attack.

“We saw some nefarious characters that may have been on our system early in the morning on Saturday,” SeaTac spokesperson Perry Cooper said in a further update on Monday. “We actually turned off our entire system to avoid anything further.”

Those flying out of the airport through Frontier, Spirit or WestJet are being advised to arrive at least three hours before the flight and print tickets at home as the software breakdown prevents this from being done at the airport.

While not always possible, those flying into SeaTac could minimize the potential for problems by traveling only with a carry-on.

“From a baggage standpoint, if you can travel without bags, do so without checking bags,” Cooper said further. Traveler Thai Un described arriving in Maui from Seattle with a family of five and finding that all the bags they had checked were not loaded onto the plane.

“We had to go to the customer service,” Un described to the Associated Press. “Sure enough, we turn around, there’s about 30 people in line, all in the same boat as we are. It was just chaotic.”

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