Police responded to the Park at Sutton Hill Apartments at 11911 Martin Luther King, Jr. Blvd around 3:45 p.m.
A preliminary investigation shows the security guard was trying to diffuse a tense situation.
"He came in to help," explained HPD's Lt. Larry Crowson.
According to investigators, there were two sisters and four children under the age of 7 inside an apartment.
One of the women went into what Crowson described as a "mental crisis."
She allegedly had a sledgehammer and was banging on the wall. Her sister went to the security guard for help. He told police he tried to reason with the woman and was able to get one child out and to safety.
"He then went back up and tried to get the other two children out because he feared for their safety," Crowson said. "He went up. The sister who was in crisis had a baseball bat, chased him out into the stairwell, struck him a couple times with the bat. At that point, he was in fear for his safety. He drew his pistol and fired one or two shots, and struck the sister."
The woman was rushed to the hospital, where she died. The security guard is cooperating with police. He has been interviewed.
Police say this case will most likely be referred to a grand jury to determine whether anything criminal happened.
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