Police responded to the 600 block of Alabama Avenue in Southeast D.C., near Ballou High School, where they say they found Wheeler suffering from gunshot wounds on May 16, just before 4 p.m.
Wheeler died from his injuries at the hospital.
Though Gray is only 16 years old, he is being charged as an adult, police said.
Police also said they consider Gray armed and dangerous. They describe him as 5 foot 6 inches, 120 pounds, with dark brown eyes and black hair in a news release.
Police are offering a reward of up to $25,000 to anyone who provides information that leads to the arrest and conviction of the person or persons responsible for any homicide committed in the District. Those with information about this case can call police at 202-727-9099 or text 50411.
Below is a map of the area where police said they found Wheeler.
WTOP’s Nahal Amouzadeh contributed to this report.
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