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AZLE (CBSDFW.COM) – Tarrant County Sheriff’s investigators are probing a fatal shooting involving one of their deputies. Kamal Dajani, 26, was killed while allegedly stabbing three family members, including a younger brother, his mother, and his grandmother.

Neighbors told CBS 11 News they are hurt by news of the attacks and death, but not surprised.

“It was something we knew could happen. It was just a matter of time before something major happened,” according to next door neighbor Amanda Paschal, an emergency room nurse who helped treat the victims until ambulances arrived.

Many neighbors heard screams and saw Dajani’s mother and younger brother, bleeding in the front yard. A 911 call brought a first responder, a deputy sheriff who was told Dajani was still attacking his grandmother inside the home.

“I saw him [the deputy] go in the house,” neighbor Blake Patterson told CBS 11 News. “I heard him scream for the kid to get down, or to get off the grandma a couple of times.”

Investigators said Deputy Christen Jarvis fired one time, killing Dajani. Three other family members went to Fort Worth hospitals with varying degrees of stab wounds. Amanda Paschal said friends have visited them today and the wounds are not life-threatening; they could return soon. “We’re just trying to make it as easy for them to come home as soon as possible,” Paschal said.

But neighbors had also worried about Kamal Dajani’s mental state. Azle police confirm three prior calls for assistance since the younger family members moved in with their grandmother when she was widowed a year ago. “We knew he had mental issues,” Patterson offered, adding, “And so there’s weird stuff, he would walk up and down the street screaming.”

Neighbors said Texas Adult Family Services had even investigated the home, but they said no action was taken. “And pretty much they had been told until he hurts somebody, they can’t do anything,” said Paschal. “They did everything they could but the system pretty much failed them.”

Texas Adult Protective Services would not comment on Dajani’s death, citing legal and privacy issues.

The deputy is identified as Christen Jarvis, 37, a former Tarrant County detention services officer. He earned his peace keeping license, then worked for the college district and White Settlement police before rejoining Tarrant County in 2012 as a deputy sheriff. He hasn’t had prior disciplinary findings, according to Tarrant County Sheriff Anderson, and is on routine administrative leave while the death is investigated.

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