UPDATED | September 9, 2016 11:57 AM

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FARMERS BRANCH (CBSDFW.COM) – A grand jury has indicted the former Farmers Branch police officer accused of killing a teenager back in March.

Former Officer Ken Johnson had already been arrested and charged with Murder and Aggravated Assault with a Deadly Weapon. Today the Dallas County District Attorney’s Office confirmed they are moving forward with the prosecution of the two cases.

It was on March 13 when investigators say Johnson, who was off-duty at the time, saw someone burglarizing a vehicle at a nearby apartment complex. When suspects Jose Cruz and Edgar Rodriguez Arevalo took off at a high rate of speed, Johnson went after them in his own vehicle.

After a car chase that ended at a gas station, Johnson fatally shot Cruz, 16, and wounded his friend Rodriguez. In a later interview Rodriguez said Johnson did not identify himself as a police officer until after the shooting. Johnson’s attorney says his client did so repeatedly, saying, “Police, show me your hands.”

After being charged, Johnson resigned from the police department. It was just days after stepping down from the police force that Cruz’ family filed a wrongful death lawsuit against Johnson and the City of Farmers Branch.

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