Two trains collided on one of Seoul's major subway lines on Friday, injuring nearly 200 passengers, police and firefighters said. No fatalities were immediately reported.
None of the injured were reported to be in a serious condition. Some of the wounded passengers were taken to one of 13 nearby hospitals, mostly for minor scratches, with one of the two train drivers receiving surgery for a fractured shoulder, officials said. Around 150 passengers are currently being hospitalized.
Some 1,000 other passengers escaped safely around 10 minutes after the collision, they added.
The collision happened at Sangwangsimni Station on Subway Line 2 at around 3:30 p.m. when a train ran into the back of another train that had stopped at the station due to a mechanical problem, they said.
According to Seoul Metro, the operator of the subway line, it was the first time that subway trains had collided in South Korea. Service on the subway line was partially restricted following the accident.
Seoul city officials said a failure in the following train's automatic distance control system (ATS) could have been the cause of the collision. The ATS should have activated when the two trains approached within 200 meters of each other.
"This accident is presumed to have been caused by a fault in the automatic distance control system," one of the officials told Yonhap News Agency by phone. "We need more investigation to know why the system broke down," the official added.
Some of the rings connecting cars of the struck train were damaged and three wheels of the other train were knocked off the track by the collision, according to Seoul Metro.
Passengers said there was no announcement telling passengers to leave the trains following the crash so they pulled emergency levers to open the subway doors and exit.
"All the passengers who were standing at the time were thrown off their feet right after the sound of a collision was heard from behind as the train was stopping temporarily," said an 18-year-old student who was aboard the rammed train at the time. "Minutes later, all the light inside the train went out and the people screamed," he said.
"But there was no announcement telling passengers to escape... So passengers groped the walls, forced the doors open and escaped by themselves."
Shortly after the accident, the Ministry of Land, Infrastructure and Transport established a central crisis center, sending railway safety inspectors to the scene.
Seoul Mayor Park Won-soon also went to the scene to orchestrate the city's response to the accident.
The accident comes as the country is still reeling from a ferry tragedy on April 16 that has left 302 people dead or missing. The 6,825-ton Sewol carrying 476 people sank off South Korea's southwestern island of Jindo, sending the nation into grief and shock. A total of 174 people were rescued in the accident.