The incident comes in the wake of a series of seemingly random attacks on strangers that have unsettled the nation throughout the summer.
It happened at about 8.22am local time on 6 September in Seoul, local media reported. The man was seen in security footage shoving his way through on a Seoul Metro Line No 2 subway car.
The crush happened at the Euljiro 4-ga station during the bustling morning rush hour. The incident has now exacerbated fear among subway riders.
Due to the mayhem, at least 21 commuters were injured and train operations came to a halt for about six minutes.
Surveillance footage secured by the Seoul Jungbu police station shows the suspect in a black hoodie and a mask aggressively navigating through passengers as he traverses the train aisle.
The man’s actions triggered panic among passengers and led to a chaotic scene inside the train and a rush towards the station exit.
As a result of the mayhem, the train halted, causing a delay of approximately six minutes, local media reports said.
After investigating and examining security camera footage, the police arrested the suspect near his residence in Seoul on Tuesday.
The unidentified man now faces charges related to causing injuries through violent actions and interfering with business operations.
The suspect claimed innocence and told police during interrogation that he was simply trying to cross the crowded train and had no intentions of causing any harm.
The police also noted he had a medical history of a mental health issues, according to reports.
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