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Blunt force trauma to the head and face resulting in multiple skull fractures contributed to the death of the 2-year-old boy killed by his father on a dark country road Saturday.
Preliminary autopsy results uncovered several cranial breaks, but the official cause of death won't be known until toxicology tests are complete, which could take up to four weeks, the Stanislaus County coroner's office said Thursday.
"Nothing definitive can be said until (the toxicology results) come back to make sure nothing was in the baby's system," said Stanislaus County sheriff's deputy Royjindar Singh.
The skull fractures are "one of the causes of death, if not the cause of death," he said.
Sergio Casian Aguiar, 27, slammed, punched, kicked and stomped his child to death, until Modesto police officer Jerry Ramar, dropped on the scene by helicopter, killed him with a single gunshot to the head, authorities said.
DNA test results released Thursday confirmed the father-son relationship. The baby's name, authorities said, was Axel.
Passers-by encountered the horrifying scene Saturday about 10:15 p.m. on West Bradbury Road, near the intersection of Blaker Road, 10 miles west of Turlock in rural Stanislaus County.
Axel's mother, Frances Lilian Casian, a teacher at El Capitan Elementary in Delhi, has been cooperative with investigators, Singh said, and is surrounded by family while dealing with the loss.
Funeral information has not been released.
Bee staff writer Michael R. Shea can be reached at mshea@modbee.com or 578-2391.
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