CHICAGO (CBS) — A 16-year-old boy accused of killing 33-year-old Shuai Guan in Bridgeport during a string of carjackings last month has been charged as an adult.

Denroy Garcia was ordered held without bail Thursday afternoon on one count of first-degree murder. He already had been charged as a juvenile with receiving or possessing a stolen vehicle and aggravated vehicular hijacking for stealing three other vehicles in the day leading up to Guan’s murder.

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Cook County prosecutors said Guan parked his Jeep Cherokee on the corner near his home at 30th Street and Union Avenue around 6:30 p.m. on Dec. 21, and left it running and unlocked, but was still holding his key fob, as he went to get his mail.

While he was at his mailbox, when carjackers pulled up in two stolen cars and double-parked in front of Guan’s Jeep. Prosecutors said Garcia got out of a Subaru Outback he had stolen just minute earlier, approached Guan, pulled something out of the pocket of his hoodie, and demanded the keys to the Jeep.

Guan handed over the key fob, and Garcia got into the Jeep and revved the engine, but could not figure out how to put it into drive. At the same time, Guan was calling 911 to report he was being robbed at gunpoint, and walked into his alley.

Seconds later, Garcia got out of the Jeep, got back into the stolen Subaru, and chased Guan into the alley, his accomplice following close behind in the stolen Audi, according to prosecutors. Garcia then fired three shots, hitting Guan at least once in the back.

Prosecutors said Guan could be heard moaning on the 911 call after he was shot.

Garcia fled the scene in the stolen Subaru, and his accomplice fled in the stolen Audi. Prosecutors said the entire incident was recorded on private surveillance video.

Police found Guan a short time later, lying face up in the alley. He was taken to University of Chicago Medical Center, where he was pronounced dead.

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“No, they didn’t take the car,” Guan’s wife, Hongyu Bai, told CBS 2’s Jermont Terry in December. “They don’t know how to drive the car.”

Later that night, officers on routine patrol spotted Garcia and his accomplice sitting in the stolen Subaru. When officers approached the vehicle, he got out and backed away slowly, before trying to run away. Officers were able to catch him and take him into custody after a short foot chase.

The stolen Subaru and stolen Audi both were recovered at the scene.

Prosecutors said detectives recovered three 9mm shell casings from the alley, and they are undergoing ballistics tests.

The hoodie Garcia was wearing at the time of his arrest also tested positive for gunshot residue. Prosecutors said it’s the same hoodie he is seen wearing on surveillance video of the shooting.

Garcia’s DNA also matched evidence collected from an Arizona Iced Tea bottle found in the stolen Audi.

Garcia was already being held in juvenile detention for stealing three other vehicles, including the Subaru and the Audi, as well as a 2010 Mercedes he stole from a Lyft driver the day before Guan’s murder.

Skyrocketing carjackings have been an ongoing crisis in Chicago for several months. The number of such crimes more than doubled citywide from 603 in 2019 to more than 1,400 in 2020, the highest totals in nearly two decades.

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CBS 2 Chicago Staff