MADISON, Wis. (AP) — A federal grand jury has indicted a former University of Wisconsin-Madison student accused of threatening people at the school, prosecutors announced Wednesday.

The grand jury in Madison indicted 32-year-old Arvin Raj Mathur on six counts of transmitting communications containing threats to injure other persons. He faces up to five years in prison if convicted on each count.

Prosecutors have accused Mathur, a former UW-Madison anthropology graduate student, of using email to threaten graduate students, staff and professors in February. He threatened to “personally stalk and kill all of your loved ones” in one email and wrote in another that he would kill their children, according to the FBI.

Prosecutors initially charged Mathur via complaint on March 8. He was arrested Friday at a Detroit-area airport after traveling from Copenhagen, where he has been enrolled at a university, court records and online jail records show.

He remains in custody in Michigan pending an arraignment in Madison. A date for the proceeding hasn’t been set yet.

Online court records did not list an attorney for Mathur. The Detroit News has reported that Mathur’s court-appointed attorney is Amanda Bashi. She didn’t immediately return a voicemail Wednesday afternoon.

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