Photo: Santa Paula Police Department

Marciela Ruiz

A California mother is under arrest for child endangerment after police allege she bound the hands of her 3-year-old son and placed a plastic bag over his head, leaving him alone in a bedroom inside a burning house.

The origin of the fire is still under investigation, the Santa Paula Police Department announced in anews release.

The fire in a first-floor living room was extinguished, and the mother and her son were taken to Santa Paula Hospital and treated for smoke inhalation.

Police, fire and arson investigators quickly began a criminal investigation.

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The father arrived and followed firefighters into the home, where he escorted his grandson outside, Det. Sgt. Allen Macias tells PEOPLE.

Police determined that Ruiz had tied the toddler’s hands and covered his head with the bag, leaving him alone in a second-floor bedroom. “He was told to stay in place, and after nothing was happening, he exited the room that he was in and found that the house was full of smoke,” says Macias.

An attorney who might speak on the mother’s behalf was not identified.

Ruiz was booked into the Ventura County jail with bail initially set at $50,000. She attempted to post bail, until detectives learned of evidence that led to an additional felony charge of arson, which led the bail to be raised to $500,000.

She remained in jail on Tuesday.

Ruiz was estranged from her husband at the time of the incident. “From what we understand,” says Macias, “there’s a nasty custody battle going on between our suspect and the child’s father.”

source: people.com