BALTIMORE (WJZ) — The reward for information on a person of interest in a fire that killed three Baltimore firefighters is up to $100,000 following contributions from the state and a local fire union.

On Saturday, Baltimore Fire Officers IAFF Local 964 announced it would be joining the local firefighters union in contributing $10,000 to the reward, upping the total to $50,000.

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An hour later, Gov. Larry Hogan announced the state would be doubling the reward to $100,000.

“As we continue to mourn our fallen heroes, we are conducting an aggressive investigation into the cause of the fire that took their lives,” he said in a statement.

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

A partial building collapse trapped six firefighters, the Baltimore division of the Bureau of Alcohol, Tobacco, Firearms and Explosives said. Three firefighters — Lt. Paul Butrim, firefighter/paramedic Kelsey Sadler, and EMT/firefighter Kenny Lacayo — were killed in the collapse.

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John McMaster was critically injured in the incident, but he was well enough to be released from Shock Trauma on Thursday.

Two others were pulled from the collapse with minor injuries.

The Baltimore office of the ATF released two images of the person of interest.

“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.

The agency offered a reward of $10,000, which was soon matched by Baltimore Mayor Brandon Scott and Baltimore County Executive Johnny Olszewski.

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Anyone with information is asked to call 888-ATF-TIPS or email ATFtips@atf.gov.

CBS Baltimore Staff