A man has been apprehended on suspicion of posting an online message threatening to kill women near Seoul's Sillim subway station, where a deadly stabbing rampage took place last week.

The Seoul Metropolitan Police Agency said on Tuesday that the man in his 20s was arrested for intimidation after he allegedly announced to an online community the previous day that he would kill 20 women in the area on Wednesday.

The suspect called the 112 emergency line to turn himself in early Tuesday, and he reportedly confessed to making the threat out of anger after seeing last week's stabbing rampage in the news.

The police also confirmed that the suspect had canceled an online purchase of the same weapon he had posted a picture of.

Investigators plan to review the suspect's recent activity to determine the motive behind the alleged crime.

Late Monday, the police were dispatched to the Sillim-dong area in Seoul's Gwanak District upon receiving a report that someone was holding a knife, but after searching the area, they determined that it was a false alarm.