The Associated Press reported that Sunday's case is at least the fourth officer-involved shooting linked to the Memphis safe taskforce, which includes federal and local agencies.
Two previous shootings in May did not involve National Guard members, while an October shooting was also tied to the taskforce.
Terracle Nelson, a cousin of Johnson, said authorities informed the family that Johnson had been shot twice in the chest.
Evaniel Johnson, the grandfather, said his grandson attended Tennessee State University, was a father, and was preparing to help lead the family construction business.
The grandfather stated he wanted to review the investigation findings and any available video footage before making a final judgment.
"I believed in him, and I know he still had so much life ahead of him," Johnson said.
"The heartbreaking reality is that he will never have the chance to enjoy what we were building together.
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That is a pain no grandparent should ever have to endure."
