Dongdaegu Station is filled with passengers waiting for trains as an electronic board displays delays caused by a train derailment, Sunday. Yonhap

"This feels like something out of a disaster movie," said Kim, a 39-year-old office worker from Seoul, as he waited inside a KTX train that had been halted at Dongdaegu Station for over two hours at 8 p.m. on Sunday. "Even if I drive now, I'll still arrive in three and a half hours, and I've already been waiting here for an hour and a half."

Meanwhile, the waiting room on the second floor of Busan Station was packed with passengers unable to board their trains. They stared anxiously at the electronic display, hoping for an announcement that departures would resume, but only the notice "delay" appeared.

"If I knew it would take this long to get to Seoul, I would have chosen a different route or accommodation, but it was frustrating to wait for hours blindly," said another passenger surnamed Lee.

On Sunday, the final day of the National Liberation Day holidays, many travelers returning home on KTX were disrupted by a train derailment.

A KTX train bound for Busan, which departed from Seoul at 4:38 p.m., had one of its wheels derail while traveling from Dongdaegu Station to Gyeongju Station.

As a result, a total of 153 trains were delayed for up to 277 minutes due to detours on general lines amid the scorching heat. Meanwhile, the 384 passengers on the derailed train were transferred to a follow-up train.

Major KTX stations, including Seoul Station, Busan Station, and Dongdaegu Station, became chaotic due to a series of delays, while the Korean Railroad Corp. (KORAIL) app malfunctioned under the heavy traffic.

Passengers criticized KORAIL for its handling of the situation and its follow-up response to the accident.

A KTX train from Busan to Seoul is filled with standing-room passengers due to delays caused by a train derailment accident, Sunday. Yonhap

"We only received a notice three minutes before departure that the train was delayed," said Park, 37, who booked a KTX train bound for Busan at 7:20 p.m. at Seoul Station.

"I couldn't afford to get a refund or find out about the express bus options," Park added.

He boarded the train, which departed about 30 minutes late, and managed to arrive at Busan Station around midnight.

KORAIL will provide additional compensation beyond the standard delay refunds, in line with consumer dispute resolution standards. If the delay exceeds two hours due to the accident, a full refund will be issued.

KORAIL will also cover taxi fares if the train arrives after the last public transportation service. Additionally, if passengers experience discomfort from standing despite having a seat ticket on an alternative train, they will receive 50 percent of the fare in addition to the delayed compensation.

"We deeply apologize to the people for the inconvenience caused by using the train," KORAIL said. "We will cooperate with related agencies such as the Ministry of Land, Infrastructure and Transport to thoroughly identify the cause of the accident and come up with measures to prevent recurrence."

The ministry completed track restoration at 5:11 a.m. Monday and resumed normal operations. The Railway Special Judicial Police, the Aviation and Railway Accident Investigation Committee, and the Korea Transportation Safety Authority are investigating the exact cause of the accident.