California mother charged with child endangerment after three-year-old dies of fentanyl overdose

A California mother has been charged in the death of her three-year-old son who died from what the authorities are calling a 'fatal level of fentanyl.' 

Jennifer Mae Niemann, 30, was charged with child endangerment, possession of methamphetamine and fentanyl on Thursday in the overdose death of her son.

Niemann was the child's primary caregiver and was present when her son died on May 4, according to the San Luis Obispo Police Department, NBC News reported. 

The toxicology results released in mid-June revealed that the child died from 'a fatal level of fentanyl in his system,' the news outlet reported. 

Though it's unclear how the baby may have ingested the toxic drug, a months-long investigation showed that the mother's 'actions allowed access to fentanyl which directly led to the child’s death,' the news outlet reported. 

Police received a call around 10:15 p.m. of an unresponsive three-year-old boy who was turning blue and not breathing at a home in the 1600 block of Mill Street in San Luis Obispo 

The boy was transported to a nearby hospital but never regained consciousness

Police received a call around 10:15 p.m. of an unresponsive three-year-old boy who was turning blue and not breathing at a home in the 1600 block of Mill Street in San Luis Obispo.

When emergency personnel arrived at home they began CPR on the infant. The boy was taken to a nearby hospital, but never regained consciousness and died later that evening. 

Officials opened an investigation into the circumstances surrounding the child’s death and an autopsy, along with a toxicology screening, was performed.

The mother was described by authorities as a 'transient' and taken into custody on Tuesday once she was located, officials said. 

She was taken to the San Luis Obispo County Jail. Her bail was set at $505,000, according to online booking records.