A 79-year-old man who caused an explosion and fire at a dental clinic Thursday in Gwangju had done so out of dissatisfaction with the clinic, according to local police.

The suspect had told police investigators that he committed the crime because he was discontent with the dental treatment he received, local media outlets reported Friday, citing officials at Gwangju Seobu Police Station.

The incident occurred at 1:14 p.m., when the suspect set off an explosion with a makeshift device in the reception area of the dental clinic on the third floor of a building in Seo-gu, Gwangju. The explosion caused a fire that forced the evacuation of some 90 people in the building.

The clinic had been mostly empty at the time, as most of the staff was out to lunch. No casualties occurred, and the fire was extinguished within 10 minutes.

The incident initially caused a terrorism scare, leading to a police strike team being dispatched to the scene.

At around 3 p.m. the police apprehended the suspect, who claimed that he intended to turn himself in. It was found that he initially fled the scene for his home, but then headed to Gwangsan Police Station where he was taken in.

Officials are currently holding the suspect for questioning and will conduct an investigation into his specific motives and how he made the explosive. They will also request an official arrest warrant from the court.