A teenage boy has turned himself into the police for allegedly threatening to sexually assault a minor in an online post, police said Tuesday.

The high schooler turned up at a police outpost in Guro-gu, southwestern Seoul, confessing to posting the notice, according to Seoul Guro Police Station.

A notice, published in an online forum at 1:30 p.m. on Tuesday, read that a person would sexually assault an elementary school girl aged 8 to 13 near Gangnam Station. The original post has been deleted.

The police was alerted to the post at 2 p.m. and dispatched patrols. Police in the districts of Gangnam, Seocho and Suseo deployed patrol cars to elementary schools within their jurisdictions.

“The high school student, who is a minor, was delivered to the police and the student will be charged after further investigation into the facts and the reasons for posting," a police officer told local media.