Authorities in Pennsylvania are searching for a university student who allegedly made a threat on Twitter to kill classmates in a reference to the 2007 Virginia Tech massacre, the Pittsburgh Post-Gazette reported.

All Saturday activities at Pennsylvania State University-Beaver in Center Township, Pa. -- about 30 miles northwest of Pittsburgh -- were canceled as state police and the FBI searched for 21-year-old Michael Dewight Mollett.

"We decided to take the precautionary step of closing the campus for classes and activities today," Chancellor Gary Keefer said in a statement on the university's website. "We have alerted all students and staff, and are asking them to avoid campus today. We also are asking any students who can go home for the weekend to do so."

Posts from late Thursday on a Twitter account apparently belonging to Mollett, who identifies himself as a point guard on the school's basketball team, make reference to "creepin tonight," people being "scared as hell" and having a "VT day," an apparent reference to the April 2007 massacre of 32 people at Virginia Tech University by student gunman Seung-Hui Cho, who later turned his gun on himself.

Mollett is wanted on charges of harassment and making terroristic threats.

He was arrested by Penn State Beaver campus police last month on charges of misdemeanor indecent assault and defiant trespass. He has previously been charged with receiving stolen property, reckless driving and fleeing an officer.

Mollett's mother, Pamela Lawton, told KDVA-TV on Friday that he has "emotional problems" but she has "never known him to be violent."