Man in his 20s arrested for brandishing a knife on the street... Emergency hospitalization ordered (Incheon, South Korea)

A man in his 20s was arrested by police for brandishing a knife on the street. On the 20th, the Incheon Western Police Station in South Korea arrested a man in his 20s, A, on suspicion of violating the Violence Acts Punishment Act at around 2:50 pm the previous day.
On the 19th of this month, at around 11:30 a.m., Mr. A was found dead on the street near the Cheongna International City apartment complex in Seo-gu, Incheon, brandishing a knife he was carrying.
The video footage taken by a citizen who witnessed Mr. A at the time showed Mr. A repeatedly swinging what appeared to be a bladed weapon around with great force.
Police seized the knife and hospitalized Mr. A for emergency treatment, and are currently investigating the exact motive for the crime.