MODESTO – Toxicology tests came back negative Thursday for the Turlock man who savagely beat his young son to death last month, adding to the mystery of why a father would commit such a heinous act.
Sergio Casian Aguiar, 27, had no drugs or alcohol in his system that might help explain his behavior, said Kristi Ah You, Stanislaus County chief coroner.
Aguiar killed his 25-month-old son, Axel, on June 14, the night before Father’s Day, on a dark country road 15 miles south of Modesto.
Confronted by two passers-by, Aguiar only stopped kicking the child when a Modesto police officer shot him in the forehead, killing him where he stood.
The boy later was pronounced dead at Emanuel Medical Center in Turlock. It took DNA testing to positively identify him.
The crime shocked the community with its brutality and generated reaction from around the world.
Investigators and co-workers said Aguiar had no criminal history or signs of mental illness, though witnesses on the night of the attack said Aguiar spoke of “demons” within his son.
Aguiar worked in the meat department at a FoodMaxx store in Turlock and recently had separated from his wife, Frances Lilian Casian, a kindergarten teacher in nearby Delhi. Casian was in Southern California for the weekend when the attack unfolded on West Bradbury Road, authorities said.
