3 Baltimore firefighter deaths being investigated as homicides

Baltimore authorities are investigating a devastating January fire that left three city firefighters dead and a fourth critically injured as a homicide, according to local officials and reports.

The firefighters were responding to a blaze at a vacant, three-story row home on South Sticker Street on the morning of Jan. 24 when the building partially collapsed, the Baltimore City Fire Department said at the time.

The Baltimore field office of the Bureau of Alcohol, Tobacco, Firearms and Explosives (ATF) announced Wednesday that the fire is now being labeled as "incendiary," meaning someone started it deliberately. 

"The incendiary classification is an important step forward in this investigation. We will continue to work alongside our partners to ensure a complete and thorough investigation is completed," ATF Baltimore Special Agent in Charge Toni Crosby said in a Wednesday statement, as FOX 45 Baltimore first reported.

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ATF Baltimore in February released surveillance footage of a person of interest in the fire and announced a $100,000 reward for information leading to the person's identity. The person of interest has since been identified and "no additional tips from the public are needed," the agency said.

Baltimore City Fire Department Chief Niles R. Ford said during a news briefing on the day of the incident that three firefighters had been working to rescue a fourth member of their department who was trapped inside the home when they were injured. 

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Responders later pulled one firefighter out of the house, followed by two others once they cleared piles of debris. 

The Baltimore Fire Department identified the firefighters who lost their lives as Lt. Paul Butrim, Firefighter Kelsey Sadler and Firefighter Kenny Lacayo. Firefighter John McMaster was later released from the hospital, according to WBAL-TV. 

"Thoughts of Lt. Butrim, Lt. Sadler and Firefighter/ EMT Lacayo have been present in our minds every step of the investigation," Crosby said in his statement. "We would like to thank members of the community who contacted ATF and our partners with information, as well as for their outpouring of support for the Baltimore City Fire Department and the loved ones of these fallen heroes."

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The Baltimore Fire Department identified the firefighters who lost their lives as Lt. Paul Butrim, Firefighter Kelsey Sadler, and Firefighter Kenny Lacayo. Firefighter John McMaster remains in the hospital in critical but stable condition, the department said.

The Baltimore ATF, Baltimore Fire Department, Baltimore Police Department and Maryland Office of the State Fire Marshal are working together in an ongoing investigation into the incident.

Fox News' Stephanie Pagones contributed to this report.