An LGBTQ Co-op poster on a whiteboard in Vanderbilt Hall was intentionally burned Friday night, initiating an investigation by both the Yale Police Department and the New Haven Fire Marshal, according to Berkeley Master Marvin Chun.

An unidentified person set fire to a poster advertising Pride Month in Entryway F of Vanderbilt, in the Berkeley side of the dormitory that houses Berkeley and Branford freshmen, Chun said in a Sunday email to Berkeleyites. Chun told students that the LGBTQ Co-op peer liaisons are available to speak with any students troubled by what he called “an insensitive and cowardly act.”

“My heart sank when I first heard this news, and I immediately thought: ‘How could this be happening?’” Chun wrote in his email. “Whether the individual intended to send a hurtful message, or simply did it out of thoughtlessness, once the act had been committed the burnt poster was out in Vanderbilt for everyone to see, and thus it hurt members of our community.”

Chun said in his email that the incident made him feel more “personally aggrieved” than he ever had felt before as Berkeley master In a separate email to the News Sunday night, he said that, given there was no fire in the entryway, “it seems unlikely to have happened accidentally.”

Co-op co-coordinator Ryan Mendías ’13 said the Lesbian, Gay, Bisexual and Transgender community is at its most visible in April, which is celebrated as Pride Month at Yale, and that the vandalism of the poster on the first day of the month may have deeply effected some LGBTQ Yalies.

Yale Police Department Spokesman Lt. Steven Woznyk said there is no security camera footage of the incident which could indicate whether the poster was chosen on purpose or randomly vandalized, but YPD investigators will begin to try to locate and speak with potential witnesses Monday. This incident, he added, is an uncommon crime for the department to investigate: the YPD has only dealt with minor, unintentional fires on campus related to cooking, smoking materials and trash can fires in the recent past.

Despite the ambiguity of the incident, Mendías said Co-op members were impressed with Chun’s response, adding that the University must take a strong stand against homophobia.

“The co-op’s primary concern is to emphasize that Yale is an open place for every member of our community,” Mendías said.

Maria Trumpler, the director of the Office of LGBTQ Resources, said she was pleased by Chun’s response to the incident, and that all of her office’s peer liaisons have reached out to Berkeley freshmen.

“I hope everyone can view this with a calm perspective and look beyond what happened, toward reinforcing the values that we all share — respect, inclusion and community,” Chun said.

The LGBTQ Co-op celebrates “Gaypril” as its pride month, although the national Lesbian, Gay, Bisexual, and Transgender Pride Month is held in June.