D.C. police have arrested a third teenager in the fatal shooting last August of Osman Al-Akbar, 19, authorities announced Tuesday.

Malachi H. Hargrove, 19, turned himself in to police late Monday morning, police said. Hargrove, a Northeast D.C. resident, has been charged with first-degree murder in connection with Al-Akbar’s death.

Officers initially responded to the 2600 block of University Place NW about 1:40 a.m. Aug. 17, 2011, to investigate a report of gunshots. They found Al-Akbar lying in the street. He had sustained multiple gunshot wounds and was pronounced dead at the scene.

Police arrested two men — Northwest resident Rashid Caviness-Bey, 19, and a 15-year-old Capitol Heights youth — shortly after Al-Akbar’s slaying. Authorities charged both of them with first-degree felony murder while armed and carrying a pistol without a license.