A 5-year-old autistic boy who authorities said was tied down and given large doses of medicine by his mother died of blunt force trauma to the head, an autopsy report said.

According to the report that was released Wednesday, Brandon Williams suffered a number of injuries including a 3 1/2 inch linear skull fracture, contusions and abrasions to his head, chest and abdomen, and retinal hemorrhages among other things.

The report also mentioned that numerous hypopigmented macules were found all over the boy’s body. Macules are discolored skin lesions.

A toxicology test run on the boy detected the presence of acetaminophen, which can be toxic to the liver and is often found in pain, sleep, cold and fever-reducing medications; and diphenhydramine, which is an antihistamine that affects heart rate and blood pressure.

Brandon was found unresponsive in his bed at his Northwest Side home in March after officials said at the time that his mother, Diane Marsh, gave the boy a large dose of medicine.

Responding paramedics found scars on Brandon’s wrists and ankles from having been bound, and severe burns on his feet from having been dipped in scalding water.

Marsh told authorities she took those actions to keep Brandon under control when he acted out.

Brandon was pronounced dead at the hospital and his mother and her two roommates — Flower Tompson and Mark Lee Moss — were arrested in connection with his death.

Five months before Brandon’s death, Child Protective Services workers tried unsuccessfully to locate the boy and his mother after school officials reported that he had stopped showing up for class.

However, a week before Brandon’s death, a Pima County sheriff’s deputy had contact with the family because a relative filed a missing persons report on Marsh, according to Star archives.

The deputy noted at the time, Brandon’s feet and legs were heavily bandaged but Marsh explained that away by saying Brandon had fallen into gravel and was cut up by cacti.

According to the sheriff’s department, the deputy planned to file a report with CPS, but her report was not sent because it was not transcribed until the day after Brandon died.

Marsh remained in jail Wednesday evening in lieu of $1 million bond. She is being held on one count of first-degree murder and four counts of child abuse.

Tompson also remained at the jail and is being held on $500,000 bond. She is facing four counts of child abuse.

Charges against Moss of failing to report the neglect of a minor were dismissed.

Contact reporter Alexis Huicochea at 629-9412 or ahuicochea@azstarnet.com.