PHILADELPHIA (CBS)—The man who confessed to killing four men in Pennsylvania was allegedly barred from the campus in which he attended due to complaints filed against him, a source tells CBS3.

Cosmo DiNardo, 20, attended Arcadia University, located in Glenside, PA in the fall of 2015.

According to the university, DiNardo did not sign up for classes for future semesters after 2015.

However, a source close to the university tells CBS3 that DiNardo did in fact return to the campus a year later during the fall and complaints were filed against him.

According to the source, students and staff said DiNardo was acting weird, and saying things that made those he talked to feel uncomfortable and uneasy.

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It’s unknown if the police were called but the source did say that a certified letter was sent to the DiNardo family saying that he was no longer allowed on the campus property.

The parents later replied to the university’s letter, stating that their son was not a threat but that he wouldn’t step foot back on the campus, said the source.

It’s believed that DiNardo obeyed the university’s wishes.

Police sources tell CBS3 that DiNardo has exhibited violent tendencies in the past.

A friend of DiNardo’s who spoke on condition of anonymity claimed that he was never known to be violent, but something happened with him in the last here.

“I’ll tell you that he was normal up until last year. He was in a quad accident and hit his head and was stranded for a day or so with a brain bleed. He had frontal lobe damage,” the friend said.

Authorities first arrested DiNardo on Monday on an unrelated gun charge dating from February, accused of illegally possessing a shotgun and ammunition after being involuntarily committed to a mental institution.

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His father bailed him out, but he was jailed again later in the week on the stolen-car charges, and bail was set much higher, after a prosecutor said he was a danger to the community because he had been diagnosed as schizophrenic.

On Wednesday night, District Attorney Matthew Weintraub announced that human remains were found on the 90-acre property owned by the DiNardo family. The body of Dean Finocchiaro, 19, was positively identified.

Thursday afternoon, DiNardo confessed to killing 19-year-old Jimi Patrick, 19-year-old Dean Finocchiaro, 21-year-old Tom Meo and 22-year-old Mark Sturgis.

In exchange for his confession, prosecutors would be taking the death penalty off the table, said attorney Paul Lang, who is representing DiNardo.