The child has not been identified publicly but the school district and the police have identified them, according to the release.
Students had been named in a "threat list" shared on social media on Wednesday, Oct. 2, the SDCY administration detailed in a statement on its website.
The threats prompted SDCY to cancel all outdoor activities and boost police presence in the district.
The 13-year-old has been suspended and could possibly be expled, York City Police Commissioner Michael Muldrow explained.
The student will also face charges, Muldrow said.
"As always, we are thankful for the tips and cooperation that made this (resolving the issue so quickly) possible," Muldrow said in a news release, "and while incidents like these are always troubling, we are heartened by the juvenile's willingness to take accountability (once identified)."
Check back here for possible updates.
Click here to follow Daily Voice Newberrytown-Lewisberry and receive free news updates.