"There were no obvious signs or cause of death," Albuquerque police spokesman John Walsh said Saturday after receiving the autopsy results from the state Office of the Medical Investigator.
Blood and toxicology tests were still pending, as were other advanced techniques that could yield clues as to how the unidentified boy died. It wasn't clear when they would be complete.
The body of the 3- to 5-year-old boy was discovered Friday by a woman who had taken her own children to the city's Alvarado Park and spotted a shoe sticking out of the sand.
Stuffed teddy bears, toy trucks and flowers were placed as a makeshift memorial at the base of the playground equipment at Alvarado Park where the boy was found.
About 50 police investigators went door-to-door Saturday asking neighbors for help in identifying the boy but came up empty-handed, Walsh said.
"No one has stepped forward as parent, guardian or caretaker or any other relationship with this child," Walsh said. "Anybody who has seen or heard of any, anything, involving a child in that area, we want them to call us."
The 38-pound boy was wearing a red shirt with the image of a truck on the front, black nylon pants with red stripes and black shoes. He had short straight black hair and was 3-feet, 2 inches in height, according to Walsh.
Albuquerque Police Chief Ray Schultz said Friday his department hadn't had any reports of missing children in the 24 hours before the body's discovery.
Forensic experts who exhumed the body told police that the boy could not have been dead longer than 48 hours, Walsh said.
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