OAKLAND (CBS SF) — The family of a man shot by an FBI agent in Oakland last month held a rally Monday to demand justice.

Jonathan Cortez was shot and killed in East Oakland on September 13th at about 3:30 p.m. in the afternoon on the 2500 block of Fruitvale Avenue as authorities served a search warrant.

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The FBI said Cortez was armed at the time of the shooting. The agent involved was part of a U.S. Marshal’s task force.

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Cortez’s family is searching for answers.

“I ask all to reach out and try to find out — anybody involved; anybody who has any other footage — please come forward so we can find out why my nephew was killed,”  said Cortez’s uncle, Johnny Wong.

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The family of Jonathan Cortez recently held a funeral for him.