A mixed martial arts fighter with a history of gang affiliation is under police investigation after choking a civilian participant unconscious during a YouTube broadcast and leaving him unattended.

Incheon Seobu Police Station announced that it is investigating the 36-year-old martial arts fighter, identified as A, on charges of assault causing bodily harm.

At around 4:00 AM yesterday (September 6), A choked a man in his 20s, B, using a technique known as a guillotine choke at an officetel in Cheongna-dong, Seo-gu, Incheon, causing him to lose consciousness.

At the time, B lost consciousness after his head struck the floor hard, but A slapped both of his cheeks, said, "Let him sleep it off," and left him unattended.

The assault by A was broadcast live on YouTube, prompting netizens to post comments such as, "Shouldn't you call 119?" and "A professional fighter shouldn't use such techniques on a civilian."

Upon coming across the footage, the police launched an investigation, booked A, and plan to continue additional investigations while contacting the victim's side.

B is currently receiving inpatient treatment at a hospital, and it was reported that he has shown symptoms of paralysis in parts of his body.

It is understood that B was a viewer of the YouTube channel and visited the officetel after communicating with the YouTuber.

A was previously affiliated with a gang managed by the police, but is known to have been removed from the management list.

Police stated, "We plan to proceed with the investigation while monitoring the victim's condition," and added, "We also plan to determine whether other individuals present at the scene during the YouTube broadcast conspired in the crime."

Reported by Jung Da-eun | Video by Lee Eui-seon | Graphics by Yang Hye-min | Produced by SBS Digital News