An elementary school teacher in Seocho-gu, southern Seoul, took her own life in a classroom Tuesday morning, the Seoul Metropolitan Office of Education said late Wednesday.

The teacher, whose identity has been withheld, reportedly killed themselves before school started in the morning, according to reports. Local media has reported that the teacher was a 23-year-old woman who passed the teacher certification test earlier this year.

It added that students had not yet been informed of the teacher’s death, citing the potential of emotional damage. No students witnessed the scene, the education office added.

The office added that police are currently investigating the case to determine the time of death, and they had yet to determine the exact cause.

The office further added that no suicide note had been found at the scene, declining to comment more on the issue. The Seoul Metropolitan Office of Education also said it would offer support for students and teaching staff experiencing trauma.