By Mike DeNardo

PHILADELPHIA (CBS) – Detectives are trying to find out why a professor at Chestnut Hill College apparently committed suicide right before class.

The professor’s jump to his death happened in front of several horrified staff members. It was about 5:30 in the evening on Wednesday right before Rudolf Alexandrov, a 71-year-old adjunct math professor, was set to begin class.

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Contradicting an original report that Alexandrov killed himself during class, Chestnut Hill College spokeswoman Kathleen Spigelmyer says no students, but several staff members saw Alexandrov approach the second-floor railing in St. Joseph’s Hall.

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“It happened very fast.  The one staff person and the security guard were with Professor Alexandrov and they were trying very hard to talk to him so that he would not take his life.”

Instead, he jumped headfirst. Police say Alexandrov had a history of depression and suicidal thoughts. Spigelmyer says the close-knit campus community is in shock, and that counseling is available for students and staff.

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Reported by Mike DeNardo, KYW Newsradio 1060