Police said Monday they have sought arrest warrants for six subway officials involved in the collision of two subway trains in Seoul early this month.

A train rammed into the rear of another that had stopped at Sangwangsimni Station on Subway Line 2, the capital city’s busiest route, on May 2, leaving 391 passengers with bruises, cuts and sprains. No fatalities were reported.

With a signal error blamed for the collision, the six are suspected of neglecting their duty of properly managing the signal, police said. According to police and Seoul Metro, the signals had remained defective since April 29 when the operator updated its signaling system on Line 2.

Four of them, in particular, failed to fix the problem even though they discovered or heard about the signal error hours before the accident, police said.

Also among the six was a traffic controller who allegedly failed to direct the driver of the first train to recover normal speed even though the distance between the two trains was becoming dangerously close and to let the driver of the following train know that the proceeding train was stopping at the station.

Police booked two others, including the driver of the proceeding train, without physical detention.

The driver, a 49-year-old surnamed Park, did not report to his superiors even though his train departed one and a half minutes later than usual due to the screen door system malfunctioning at the station.

The accident came as the country was still reeling from a ferry tragedy on April 16 that has so far left more than 300 people dead or missing.

ng an estimated 476 people sank off South Korea’s southwest coast, sending the nation into grief and shock. A total of 172 people were rescued. (Yonhap)