Rail traffic connecting Busan and Seoul resumed normal operations on Sunday, less than 24 hours after collisions involving three passenger trains in a southeastern city, officials said.

Officials of Korea Railroad Corp. (KORAIL) said an early KTX bullet train leaving Busan, about 450 kilometers southeast of the capital, for Seoul departed on schedule at 5 a.m. Sunday.

They said other passengers also left for their destinations on time, except for one Mugunghwa train that had maintenance issues and was delayed for 10 minutes.

On Saturday, a KTX train and a non-express Mugunghwa train, both bound for Seoul, collided near Daegu Station, about 300 kilometers southeast of Seoul, at 7:14 a.m, causing eight passenger cars from the bullet train and the lead cab from the Mugunghwa train to derail. Later in the day, another KTX train, traveling in the opposite direction toward Busan, crashed into the derailed KTX train, causing further disruption.

KORAIL reported no serious injuries or casualties from the collisions. It said the KTX train and the Mugunghwa train in the initial collision were each carrying about 270 passengers, while the third KTX train had about 600 passengers at the time of the accident.

According to KORAIL officials, the Mugunghwa train was departing from Daegu Station, while the KTX train, which doesn't stop at Daegu, was passing through the station.

The main causes of the collisions are presumed to be the Mugunghwa engineer's carelessness in checking railway conditions and signals, as well as a local controller's failure to notify the Mugunhwa train to wait as it approached on the main line, said KORAIL.

Railway control systems and signals were working normally at the time of the collision, according to KORAIL officials.

Shortly after the traffic was normalized, the company removed two ranking officials and the chief of the Daegu Station from their positions, holding them responsible for the accident.

The accident disrupted railway services between Seoul and Busan late into the night. KORAIL officials said a KTX train scheduled to leave Busan at 10:50 p.m. Saturday was delayed by an hour and 40 minutes, while other passenger trains were pushed back by as many as three hours. Some trains leaving Seoul for Busan were delayed by more than four hours, according to KORAIL. (Yonhap News)