After several Harvard staff members raised concerns about not receiving notice of an alleged attack outside Lamont Library early Tuesday, the Harvard University Police Department (HUPD) conceded that a formal advisory e-mail should have been sent.

An alert was sent on Tuesday afternoon to all Harvard undergraduates, while other members of the community were not notified of the incident until Friday.

“It is outrageous that I, or more importantly my friends who work in Cambridge in the Lamont Library, were not informed,” said Wendy M. Brown, a library assistant at the Medical School. “Is Harvard just trying to save face by not telling its employees about this?”

Brown said that she only heard of the incident by word-of-mouth. Her boyfriend, who is also employed at the Medical School, happened to overhear a conversation concerning the attack last week while in Cambridge, she added.

Brown said that she was initially afraid of being dismissed as “paranoid” or “stressed out,” but that the 10 Harvard Library staff members she then contacted told her they had not received an alert from HUPD either.

In response to an e-mail Brown sent to HUPD asking why Harvard employees had not been informed of the incident, HUPD spokesman Steven G. Catalano replied Thursday that the public safety threat was determined to be “minimal” and that alerting undergraduates was deemed “sufficient.”

On her blog, Brown quoted her boyfriend’s reaction to Catalano’s words, asking, “Why was it deemed only necessary to inform students; do violent predators discriminate between undergraduates and employees?”

According to a Harvard Library employee, who requested anonymity because of the sensitive nature of the situation, several of his co-workers were also “pretty upset and confused” as to why HUPD only felt the need to inform undergraduates.

He said that HUPD had not replied to his e-mails as of yesterday afternoon.

But Brown said that the Chief of Police Francis D. Riley sent her a statement through Catalano Friday explaining that, in retrospect, an advisory should have been distributed more broadly to include all students, staff, and faculty.

“We regret the initial judgment not to make the advisory more broadly available,” Riley said. “ We will review our advisory distribution procedures to ensure that future incidents are handled appropriately.”

Catalano declined to add to Riley’s initial statement last Friday.

—Staff writer June Q. Wu can be reached at junewu@fas.harvard.edu.