A female resident of Peabody Terrace reported to police that she witnessed a man masturbating in the hallway of building #20 on Monday, Sept. 5.

The victim reported that she observed the man masturbating as she entered the building at approximately 12:25 p.m. She described the suspect as a six-foot-tall, thin, black male with short hair in his early 20s.

Harvard University Police Department (HUPD) Spokesman Steven G. Catalano said that there is currently an ongoing investigation to locate the suspect.

Catalano said that while this was not the first time that such an incident has occurred, it is rare that they take place inside Harvard buildings.

“Occasionally these incidents do occur,” he said. “It doesn’t happen often but every now and then you will come across an incident where someone is exposing or touching themselves in public. But I can’t recall the last time it was inside a building.”

It has not yet been determined how the suspect entered the building. A community advisory released by HUPD, however, urged members of the Harvard community “not to allow anyone they don’t recognize to ‘piggyback’ with them through a locked door.”