MCMINVILLE, Ore. — A prosecutor in Yamhill County says investigators may never know why a 33-year-old man rushed into a McMinnville convenience store last weekend and fatally stabbed a Linfield College athlete.

District Attorney Brad Berry told KGW-TV Tuesday that toxicology reports are being expedited, and officers are still examining surveillance tapes for clues to the death of Parker Moore.

But Berry says it may never be explained in a satisfying way. Investigators say they’ve found no motive, and no evidence that Moore and his attacker knew each other, or quarreled.

Police shot and killed the attacker, Joventino Arenas, as he returned to the convenience store Saturday. They said he showed a knife. Relatives of Arenas told KGW he was a Spanish speaker and was trying to surrender it to officers.