BALTIMORE (WJZ) — The Bureau of Alcohol, Tobacco, Firearms, and Explosives is seeking a person of interest in connection with the fire on South Stricker Street that killed three firefighters.

The agency released these images below and announced a $10,000 reward for information that helps to identify the person.

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“The individual we are seeking to identify may have important information that could aid in this investigation,” said ATF Baltimore Acting Special Agent in Charge L. C. Cheeks, Jr. “We ask that anyone who knows the identity of this person come forward so Special Agents and investigators can continue efforts to find the cause of this tragic fire.”

An official with the ATF said via a press statement on Friday that “the brave men and women of the Baltimore City Fire Department are always ready to respond when the people of Baltimore need them. Now it is our time to be there when they need us.”

On Thursday, the presidents of two Baltimore fire unions shed some light on why Lt. Paul Butrim, Lt. Kelsey Sadler, and Kenny Lacayo were among the firefighters who entered a burning house in the 200 block of South Stricker Street.

The fire union presidents said there were reports that people were inside the building.

“This fire came out with multiple calls, reports of people trapped,” Josh Fannon, the president of  Baltimore Fire Officers IAFF Local 964, said.

Rich Langford the president of Baltimore Firefighters IAFF Local 734 echoed the same sentiment.

“They answered the call,” Langford said. “They answered the call of people trapped.”

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In a city with thousands of abandoned rowhomes, the union presidents told WJZ that firefighters constantly find people living in them.

An official with Local 734 shared pictures of people setting up and then settling in at vacant homes.

Just two days before Monday’s fire, there was an almost identical fire just a block over from South Stricker Street. Fallen Firefighter Kenny Lacayo responded that day.

Fannon said there was just one difference in the buildings of Monday’s fatal fire versus the fire from over the weekend.

“The floors didn’t give out,” Fannon said. “You just never know. It’s horrific. It’s tragic.”

The ATF has taken the lead on the investigation, but on Friday, the state fire marshal, Brian Geraci told WJZ that the investigation at the site of the fire may wrap up Friday.

Geraci says all the agencies will then meet and review their information to decide the next steps.

The housing department said the rowhome that’s the site of the fire along with the two next to it will eventually be torn down.

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Anyone with information on the person of interest or the case can call the ATF at 888-ATF-TIPS (888-283-8477) or ATFtips@atf.gov.

Ava-joye Burnett