LOS ANGELES (CBSLA.com) — Sheriff’s investigators said Tuesday a man killed by deputies in Compton July 28th was not involved in a carjacking and pursuit.

According to the sheriff’s department, an armed carjacking suspect led deputies to the neighborhood where Donnell Thompson Junior, 27, was shot and killed.

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The sheriff’s department investigation determined the suspect was already in custody when Thompson was gunned down.

“Why would SWAT and dogs have to surround a man”who weighed 130 pounds and stood about 5 feet 3 inches tall?” asked Matrice Stanley, Thompson’s oldest sister.

“We share the concerns of the family,” said Captain Steven Katz of the sheriff’s Homicide Bureau. “The Sheriff’s Department is deeply concerned.”

Katz also confirmed Thompson had the mental capacity of a 15 year old.

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The deputy who fired the shot is now on desk duty, pending an investigation.

The district attorney’s office is investigating.

Black Lives Matter organizers said Thompson was “unarmed and wrongfully killed.”

“Our police and our sheriff’s department can longer be allowed to police themselves,” said Dawn Modkins of Black Lives Matter.

Modkins is calling for the LA County Board of Supervisors to push forward with plans for a civilian  commission to oversee the sheriff’s department.

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