1. The explosion occurred at a subway station to the south of Seoul on Monday evening.
2. The YTN TV network originally reported the blast, and an operator of the South Korean train network confirmed there was a problem with the electrical insulation on the train.
Local emergency official Yoo Hyung-gi said the damaged electrical insulation device was what triggered the explosion at a station in Gunpo city. Operations later resumed at the station.
3. Earlier this month a subway train in South Korea hit the back of train at a station in Seoul, injuring around 240 people.
More details to follow.