KEARNEY, Neb. (AP) — Campus police have arrested a 19-year-old student suspected of posting a threat to use explosives at the University of Nebraska at Kearney.

The university’s library was briefly evacuated on Wednesday after the anonymous threat was posted on a social media app. The university says the social network Yik Yak cooperated with university police in tracking the post.

The university says the suspect, Matthew Skinner, is a freshman from Ogallala. Buffalo County records said he remained in custody on Friday. Online court records don’t yet show that he’s been formally charged.