COLUMBIA, Mo. (AP) — Prosecutors have charged a third Missouri man with posting online threats to attack a college campus.

Nineteen-year-old Tyler Bradenberg, of St. Louis, was charged Thursday with a felony count of making a terrorist threat. An arrest warrant has been issued for him.

Authorities say Brandenberg posted “I’m gonna shoot up this school” on the anonymous messaging app Yik Yak on Wednesday. It was apparently aimed at the Missouri University of Science & Technology in Rolla, where he studied chemical engineering for a semester last fall.

A Rolla detective says Brandenberg admitted he posted the threat. An S&T spokeswoman says technology was used to try to make it appear the post was made from the Rolla campus, but it wasn’t.

The threats follow protests over the University of Missouri’s handling of racial issues that helped force two top officials to resign.