Just days after the tragic mass shooting at Umpqua Community College in Oregon, Philadelphia colleges have alerted their respective communities to be on guard Monday following a bulletin from federal authorities.

Drexel University explained that “the FBI has notified all Philadelphia area colleges and universities about a recent social media posting threatening violence at a Philadelphia area college or university on Monday, Oct. 5.” The school went on to say that “the FBI has seen similar media postings throughout the country” following last Thursday's tragedy.

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That posting appeared to have been made on the website 4chan's Robot9001 message board, where posters focus on their status as "beta" males. Posters see the world as divided into "Alpha" males -- who are brash, popular and attractive to women and "beta" males, who are the opposite. Many however, see that designation as arbitrary and imposed upon them by a larger society.

Authorities were investigating whether Chris Harper-Mercer, the suspect in the Oregon attack that killed nine, posted a warning on the Robot9001 message board ahead of his attack. 

In the warning, which was posted Friday, Harper-Mercer is referred to as a "martyr" in the "Beta Rebellion." 

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"If you are in that area, you are encouraged to stay at home and watch the news as the chaos unfolds," the Philadelphia threat read. "His sacrafice will echo throughout the nation." 

The nation is still reeling after the campus shooting last week. Harper-Mercer later died of a self-inflicted gunshot wound, according to the sheriff there in Roseburg, Oregon.

Similar alerts were posted on websites for the University of Pennsylvania, Temple University, and other local colleges. 

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For its part, Penn said that the ATF notified them of threats against “an unspecified university near Philadelphia” that involve a specific time: 2 p.m. Monday.

Penn said that while authorities have “no knowledge of any specific threat,” the university is "working closely with law enforcement “in an abundance of caution.”

The unspecified threat against Philadelphia colleges recalled last May’s frightening evacuation of Community College of Philadelphia. That incident occurred after cops say a student brandished a gun following an argument in class.