A police officer who used a stun gun on an armed suspect will not be held responsible for the man's subsequent death after autopsy results pointed to sudden heart failure, according to the Gwangju Police on Monday.

According to officials at the Gwangju Bukbu Police Station, the National Forensic Service who conducted the autopsy found that the suspect had suffered sudden cardiac death. SCD refers to natural death from an unidentified cause within a short period of symptom onset, often with multiple causes.

The investigation found the voltage and the level of the stun gun were both within the normal range at the time of use. Based on the findings, and the fact that the suspect had been threatening a person's life at the time, police said using the stun gun was appropriate and they would not pursue disciplinary actions against the officer in question.

The suspect, a man in his 50s, had attacked his son with a knife at around 5:48 p.m. on April 23 of this year in Buk-gu, Gwangju. Police who arrived on the scene found the suspect sitting on the victim's body with the weapon and shocked him with the stun gun to overpower him.

The suspect was being transported to a police station for questioning when he suddenly started experiencing breathing issues, eventually falling unconscious and dying. His family told police that the suspect had underlying heart problems.