JACKSONVILLE, Fla. -

A Jacksonville Fire and Rescue spokesman says the department learned about some firefighters' questionable behavior at a fundraiser last week from other firefighters.

A JFRD district chief and a lieutenant are also being questioned for their part in the event held at the Whiskey River nightclub that raised $75,000 for the family of a firefighter who died earlier this year doing an off-duty job.

Photos of the event show a woman Channel 4 was told was a JFRD lieutenant with only the straps of her bunker gear covering her breasts.

The images that surfaced on 904HappyHour.com are now the focus of an internal investigation in which JFRD policies may have been violated.

In one photo, a firefighter wearing bunker gear and a helmet gets what appears to be a tip from a girl in the crowd. In another photo, two firefighters engage in what some consider lewd behavior.

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JFRD spokesman Tom Francis issued a statement Monday, saying, "We are not oblivious to the incident. We have launched an internal investigation and we are reviewing photographic evidence and conducting interviews with those involved. Our compliance officer has been made fully aware of the transgressions. JFRD firefighters should not be wearing city-issued equipment for anything other than official duty. It is unbecoming of the profession."

According to JFRD policies, firefighters are forbidden from wearing anything that identifies themselves as a firefighter in a place that sells alcoholic beverages, unless they're working in a city capacity.

Fire union President Randy Wyse was aware of the photos circulating online, but said it was yet to be determined if there is a problem.

"There’s lots of investigations that go on; that raises an issue. The department's bound to investigate a complaint," Wyse said. "They determine if something is wrong. That is yet to be seen."

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While the district chief and all the firefighters were off duty, it was unclear if the chief was expected to provide a supervisory role in enforcing city policies at the fundraiser.