A newly installed automatic immigration clearance system failed at Bangkok's two commercial gateways on Thursday night causing massive congestion among outgoing passengers.
Malfunctioning equipment shut down the automatic passport-control kiosks reserved for Thai nationals departing flights from Don Mueang and Suvarnabhumi airports, officials said.
The problem was caused by a temporary loss of internet connection, said Don Mueang's general manager Suthirawat Suwanawat. The kiosks use a connection provided by TOT Plc to access passenger information through a central database. It was registered by the Immigration Bureau.
Immigration officers had to revert to manually interviewing Thai passengers because all four kiosks at the airport were out of order, causing queues to back up.
"The kiosk malfunctions did not result in any flight delays or cancellations. They just prevented passengers from getting through immigration in a timely fashion," Wg Cdr Suthirawat said.
Suvarnabhumi airport took less of a hit due to its larger workforce, he said.
The shutdown did not affect immigration booths for foreign travellers, officials said. The system began working again at 9.30am yesterday at Suvarnabhumi and an hour later at Don Mueang airport.
TV news presenter Kasemsant Weerakun -- one passenger affected -- issued a plaintive Facebook post asking how the glitch could have hit a system that was presumably newer than those of other countries that boast clean track records.
"Thailand only: All automatic passport-control kiosks at Don Mueang airport this morning are all out of service," he wrote.
"Only two immigration officers are here. Which company is responsible for this? And why does it malfunction so often even though the system was brought in after those of other countries?"
Pol Col Krisana Phatthanacharoen, a deputy spokesman for the Royal Thai Police, confirmed the culprit as being an interrupted internet service.
But he insisted there were more than two immigration officers serving passengers at Don Mueang airport during the malfunction. He insisted more had been deployed to clear the swelling lines.
The kiosks had resumed normal operations at both airports by yesterday afternoon, according to Wg Cdr Suthirawat.
He said Don Mueang lacks the authority to directly contact TOT Plc, the internet provider, as the connections at both airports were registered by the Immigration Bureau.
Airport staff were coordinating with the bureau on ways to marshal more staff in as quickly as 20 minutes in urgent cases that may crop up in the future.
"This issue is something that must be dealt with by the internet service company and the Immigration Bureau," Wg Cdr Suthirawat said.
"We can only inform immigration officers of the problem and ask them to deploy more staff."