AURORA, Colo. – A second teenage boy has been arrested in the deadly September shooting at Southlands Mall in Aurora, according to the Aurora Police Department.

The teen – a 17-year-old whose identity will not be released because he is a minor – was arrested Wednesday on second-degree murder and aggravated robbery charges, both felonies, according to a news release.

The shooting was reported at around 9:30 p.m. on Sept. 30 in a parking lot outside the mall where a large group of people, including teens from Smoky Hill and Grandview High Schools, were celebrating homecoming, witnesses told Denver7.

First responders arrived and found Raphael Ivan Velin, 15, suffering from a gunshot wound. He was taken to the hospital, where he later died.

Investigators believe the murder occurred during a pre-planned meeting between the involved parties, according to an initial media release from the Aurora Police Department. Raphael’s mother told Denver7 she got a phone call from him earlier that evening, and he said he was heading to the mall to meet up with friends.

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 Police said four to five suspects took off after the shooting in a black four-door sedan, which was later recovered.

Last month, one of the suspects – a 16-year-old boy – was arrested after turning himself in to police. He was booked into the Aurora Jail for second-degree murder, aggravated robbery and failure to report an accident to police.

Investigators are still working to identify and locate additional suspects, as well as witnesses to the shooting. Anyone with information is asked to call Metro Denver Crime Stoppers at 720-913-7867.

Denver 7+ Colorado News Latest Headlines | November 16, 11am