BALTIMORE (WJZ) — Three Baltimore firefighters died and one is in critical condition after a vacant rowhouse that caught fire partially collapsed Monday morning, the mayor’s office has confirmed.

The firefighters killed were identified as Lt. Paul Butrim, firefighter/paramedic Kelsey Sadler, and EMT/firefighter Kenny Lacayo.

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John McMaster, an EMT/firefighter, is on life support in critical but stable condition, according to Dr. Thomas Scalea, Physician in Chief at the University of Maryland R. Adams Cowley Shock Trauma Center.

“This is a gut-wrenching tragedy for our city, the Baltimore City Fire Department, and most importantly the families of our firefighters,” Mayor Brandon Scott said. “There are no words to describe the pain and the severity of the losses we have suffered today.”

Fire crews were initially called to the scene of a two-alarm fire at a row home in the 200 block of S. Stricker Street about 6 a.m. Monday, according to the Baltimore City Fire Department.

City Fire Chief Niles Ford said firefighters went into the vacant home to fight the blaze because there were adjacent houses that are occupied.

At some point, Chief Ford said, a partial collapse occurred, trapping four firefighters inside. He said one firefighter was immediately rescued and two more were removed within an hour.

Crews worked to extricate a fourth firefighter who was still trapped underneath the rubble left behind by the collapse. Three firefighters were taken to Shock Trauma; two were in cardiac arrest when they arrived, officials said.

Lt. Butrim and Sadler were with the department for 15 years, Lacayo was with the department for seven years, and McMaster has been with the department for six years.

Butrim was the recipient of a Valor Award in 2015 by Firehouse Magazine for rescuing an unconscious child trapped in a house fire and performing CPR until EMS units arrived.

According to the Wheaton Volunteer Rescue Squad, Lacayo received a unit citation in 2018 for his life-saving actions when a pedestrian was hit by a car. He was also recognized as a top ten responder in 2016 and 2016, the squad said.

“Every day our firefighters, our first responders put their lives on the line for the sake of others,” Chief Ford said. “From this moment, we will honor those we lost today, for their bravery, their courage, their love for helping others and the respect they had for the Baltimore City Fire Department.”

This is the first line-of-duty death for the Baltimore City Fire Department since James Bethea died on Nov. 12, 2014. The 62-year-old safety officer died after he responded to a rowhouse fire, went to check on a vacant home next door and fell through the first floor into the basement. The cause of death was smoke inhalation, investigators said.

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And it’s one of the most devastating incidents in the history of the fire department. In 1955, six firefighters died while battling a fire at the Tru-Fit Clothing Company at 507-09 E. Baltimore Street, according to the National Fallen Firefighters Foundation.

The deadliest fire in department history was 1888 — seven firefighters were killed in an explosion while battling a warehouse fire on Sharp Street, according to published reports and the National Fallen Firefighters Foundation.

Fire crews remained on the scene of the fire into the afternoon. Shortly after 2 p.m., firefighters could be seen lined up outside the hospital and later they quietly escorted a white van away from the trauma center.

At 4:17 p.m., firefighters on South Stricker Street saluted an ambulance leaving the scene of the collapse.

There’s no word yet on the cause of the fire, which remains under investigation.

Governor Larry Hogan ordered flags lowered to half staff in honor of the fallen firefighters.

“Our hearts are broken for the entire Baltimore City Fire Department as three of our bravest have fallen in the line of duty,” Hogan said. “Each and every day, our firefighters and first responders answer the call and are ready to run into danger—this is our worst nightmare.”

Hogan said he has been in contact with Mayor Scott and Chief Ford, and that the State Fire Marshal and Maryland Department of Emergency Management will continue to assist the city.

Neighbors who gathered near the site of Monday’s collapse expressed their sympathies and condolences for the firefighters involved.

“I have my prayers for them and that’s all,” Shaikh Rahim told WJZ. “This is really sad. I want this neighborhood to be good, you know? No more fires in this neighborhood.”

Details provided by Baltimore City’s housing department show the building’s most recent inspection came on Jan. 4 when an inspector found the front and rear of the building were boarded up and clean.

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WJZ reporters Jessica Albert and Paul Gessler contributed to this story.

Ava-joye Burnett