A man accused of wounding a 17-year-old with a handgun, then later firing two shotgun blasts that killed the teen as he lay bleeding on a stretcher, has been charged with first-degree murder.

Dennis Atkins (search), 21, of Detroit was arrested Saturday in the June 4 slaying of Billie Rutledge (search). Atkins was arraigned Monday on charges of murder, using a firearm in the commission of a felony and two counts of assault with intent to murder.

The assault charges were filed because Atkins allegedly ordered two paramedics to step away from Rutledge before killing him.

Authorities say Atkins shot Rutledge with a small-caliber gun, then hid when the paramedics arrived and began working to save Rutledge. They were about to place the teen in an ambulance when the gunman, wearing a mask, returned and leveled a shotgun at them, police said. The paramedics escaped injury.

Police spokesman James Tate (search) would not speculate about a motive.