MEMPHIS, Tenn. (AP) — A trial for a Tennessee teenager who's accused of killing a pregnant woman and her boyfriend has started.

News outlets report Shelby Isaac's trial started Tuesday. The 19-year-old had been indicted on charges of killing Eddie Tate, Edwina Thomas and her unborn child with premeditation, along with a charge of killing Tate in perpetration or the attempt to perpetrate aggravated robbery.

Assistant District Attorney Gavin Smith argued Isaac had purchased hair weaves from Tate and set up a subsequent meeting under the guise of buying more, while intending to get her money back. Smith said Isaac fired gunshots after they pulled up in a car.

Victoria Seay was indicted on charges of aiding Isaac to avoid punishment.

Defense attorneys argued there was no physical evidence connecting Isaac to the killings.