PORTLAND, Ore. (KOIN) — A calendar featuring images from homeless camps was found inside a Portland fire station, prompting an investigation.

Portland Fire & Rescue couldn’t say on Wednesday which station the calendar was found at due to the active nature of the investigation. It’s also unclear who made the calendar.

Fire Chief Sara Boone condemned the calendar in a letter sent to fire employees earlier in the week.

“Recently, I learned of an incident that has the potential to undermine the public’s trust by dehumanizing people who live in poverty and are, at times, the most vulnerable of those we serve,” she wrote. “To be clear, it is the expectation of this administration that all employees who work at Portland Fire & Rescue will conduct themselves in a manner that does not undermine the efficiency of our operations, the good of the order and the integrity of our service to the public.”

Commissioner Jo Ann Hardesty — who oversees Portland Fire & Rescue — also sent an internal letter to fire employees rebuking the behavior, saying the calendar disparages the homeless community in East Portland.

The letter read, in part:

“Personally, as an East Portland resident, it breaks my heart to see my own neighborhood shown in this manner by the very people we depend on to save us when something wrong happens.”

The president of the Portland Fire Fighters Association Alan Ferschweiler told KOIN 6 News the calendar was insensitive but the situation was blown out of proportion and should have been handled internally.

A statement shared with KOIN 6 News by the Portland Fire Fighters Association reads:

“Recently, media reports have gone out to the public regarding a calendar created by fire fighters that involve tents and other areas of the City. Our fire stations and fire fighters work hard every day for the citizens of Portland. The number of fire fighters serving the City has remained the same, while the call volume has increased dramatically. Last year alone we responded to almost 100,000 emergency calls. The work that we do is stressful. I see it every day in the life of our fire fighters. I would not expect the public to understand, but one of the ways that professions like the military or the fire service cope with stress is through humor. The gritty realities we see every day can get grim and creating some humor around the intensity of our work relieves the stress we all feel. This is one of those times. I believe that this event should have been handled internally. This is a symptom of a workforce that works very hard for the citizens and is stretched beyond its capabilities. These fire fighters come to work and face unknown challenges and dangerous situations every day. We need to work on helping them to find healthy tools to deal with the stress.”