SAN ANTONIO – Investigators have determined mistakes were made on the night San Antonio firefighter Scott Deem was killed.

It has been nine months since the six-year veteran passed away on May 18. A new report is shedding light on what happened the night of the deadly fire at a Northwest Side shopping center.

“We lost someone over a building. Another big takeaway is that someone killed one of my firefighters," San Antonio Fire Dept. Chief Charles Hood said.

In December, 39-year-old Emond Johnson was charged with murder and arson for intentionally setting the fire that killed Deem. Johnson is accused of setting fire to the Spartan Box Gym he owned.

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A police affidavit said Johnson owed an estimated $7,000 in back rent and other debts, and was trying to escape his lease. It's believed he used a lighter to ignite a mixture of gasoline and oil inside the building.

A report by the State Fire Marshal’s Office is required in order to review the actions the department took fighting the four-alarm fire.

“The size of this fire was correct. The proper resources we called initially. But, the tactics resembled the tactics that we would use on a house fire versus the tactics and strategies we would use on something bigger. Which would involve in how we stage our trucks. How we attack the fire,” Hood said.  

A full report of more than 40 pages will be released on Friday, which will make recommendations on how to help keep people from getting hurt during fires.

Johnson is charged with felony murder, arson resulting in death, two charges of arson and bodily injury, and arson building. In Texas, a felony murder charge is punishable by up to 99 years or life in prison.