NEW YORK (AP) — A week ago, 18-year-old Nolan Xavier Wells took a boat trip with friends to celebrate the Fourth of July on an island off Mississippi’s Gulf Coast. He never came back.

Two days later, he was found dead. What happened, Wells’ parents say, is a mystery riddled with conflicting stories, implausible explanations and missing details. It is a case shadowed by the state’s fraught racial history and lingering distrust in law enforcement.