SYRACUSE (AP) -- Police say a man serving time for trying to kill a Syracuse police officer has been charged in the 2009 shooting death of a 37-year-old man gunned down outside his apartment.

Police say 22-year-old Aaron Jackson was charged Tuesday with second-degree murder, robbery and criminal possession of a weapon.

Jackson was sentenced last year to 25 years to life in state prison after pleading guilty to attempted murder. He admitted he was trying to kill Officer John Mulherin when he fired at him on Aug. 17, 2010.

Jackson was charged Tuesday in the 2009 death of 37-year-old Terrance Heyward.

Police say the case is still under investigation and there may be more suspects.

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