CHICAGO (STMW) — A 15-year-old boy was held on $2 million bond Sunday, one of two teens charged in connection with the armed robbery of an off-duty Cook County Sheriff’s sergeant that left a third suspect dead.

Judge Adam Bourgeois Jr. ordered Emmanuel Johnson, of 103rd and Corliss on Chicago’s South Side, held on $2 million bond at a hearing Sunday, the Sun-Times is reporting.

The 15-year-old boy has been charged with one count each of first-degree murder and armed robbery with a firearm in connection with the robbery, according to Chicago Police.

Devante Graham, 17, is also charged with their cohort’s death Thursday based on the theory of accountability after an off-duty Cook County sheriff’s sergeant killed a teen when he was robbed by the trio Monday night at a Citgo gas station in the 700 block of East 103rd Street, authorities said.

Deonta Mackey, 16, was armed with a 9 mm semi automatic gun when he threatened the officer’s life, and demanded he turn over his money and everything from his pockets, according to prosecutors and court documents.

Graham, who had his hands in his pockets, further motioned for the officer to hurry up, according to court records.

The officer gave Mackey money and gum while Johnson allegedly went into the officer’s car and started rummaging through the glove box, court records show.

At that point, Mackey, still pointing his gun at the officer, asked him to give him his wallet and car keys.

That’s when the officer reached into his pockets, grabbed his gun and shot Mackey.

Once the shots were fired, Graham and Johnson fled, and Johnson dropped a bag he had taken from the officer’s vehicle, according to court documents.

The entire incident was captured on nearby video surveillance cameras and the officer has identified Graham and Johnson as two of the teens in the trio who robbed him, prosecutors claim.

Johnson turned himself in to police after he saw the surveillance video aired on television, court records show.

After the shooting, many Chicago Public Schools students told authorities that the suspects had posted pictures of themselves with guns on Facebook, Assistant Cook County State’s Attorney Claire Savaglio said at Graham’s bond hearing Thursday.

Upon further investigation, detectives learned that one of the weapons in the pictures was used in the deadly robbery, Savaglio said.

The weapon has been recovered.

Graham, who also turned himself into police, is charged with first-degree murder and armed robbery. He is being held on $1 million bond.

(Source: Sun-Times Media Wire © Chicago Sun-Times 2014. All Rights Reserved. This material may not be published, broadcast, rewritten, or redistributed.)

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