An elementary school teacher was arrested for having sex with a middle school student with a mental disability. 

The 30-year-old male teacher has been charged with sexual assault of a minor with a disability and is being investigated further. 

It is reported that the teacher met the middle school student, a 13-year-old girl, through a random chat website; they met up several times for sex back in May and June earlier this year. 

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The 13-year-old posted, "I am looking for a boyfriend," and the teacher responded to the post according to the police report.

The disturbing incident came to light when the student confessed everything to her school counselor, who then contacted the police. The teacher has admitted to having had a sexual relationship with the girl. 

The police are investigating whether the 13-year-old, who suffers from mental developmental issues, can be considered to have the capacity to consent to sex. In South Korea, the age of consent is 13.