PHOENIX (AP) -- A 19-year-old man who died after two groups of people fought in the middle of a northwest Phoenix street had a pre-existing heart condition. Phoenix police say an autopsy shows Edgar Box also had an enlarged heart and that likely caused his death earlier this week. They say a toxicology report isn't available yet. Box was pronounced dead Wednesday at Phoenix hospital. Witnesses had told police that Box was jumped and beaten by the other group and collapsed when the fight was over. But police said Friday that Box suffered one minor injury, believed to have occurred when he collapsed in the street. Police say the 2 a.m. fight Wednesday was between people attending a party in a condominium unit and people who were in an apartment across the street.