Police said Thursday a woman in her 20s admitted to having abused her 3-year-old nephew, who was found dead from an apparent drowning in Naju, South Jeolla Province, Wednesday.

The accused, 25, was detained immediately for interrogation. She had reportedly been looking after the child since June after her sister, the mother of the child, found work at a factory away from their home in Naju.

She cited her anger management disorder and mental disability as having triggered what she insists was “spur-of-the-moment” violence.

The accused told police she became “angry” with the 3-year-old after he soiled his bedsheets. When she took the victim for a bath, he reportedly vomited. She then forced the toddler’s head underwater.

The woman said she attempted CPR on the child, but to no avail, and called emergency medical services for help.

While police have asked the National Forensic Service to perform an autopsy on the victim to determine the exact cause of his death, police believe the child drowned.

The woman admitted to having also beaten and choked the child prior to his death.

Upon discovery, the child had a cast on his arm, which was reportedly broken in July when the woman stomped on it while “enraged for no apparent reason.”

Police said the NFS autopsy will provide an idea of how long the abuse had gone on. Depending on whether or not the accused had deliberate intentions to kill the child, she could face a punishment of a minimum five years in jail, a life sentence or death.

Police also confirmed with medical authorities that the woman had bipolar disorder and was taking pills to control her mood. 

Police said the accused had a medical history of anger control disorder. In July 2013, she was determined to have third-class mental retardation, which applies to people with an IQ between 70 and 75. People with third-class mental disabilities are able to lead a mostly normal lifestyle, albeit with handicaps in learning that may keep them from working. An IQ between 90 and 110 is average.

The accused was unemployed and living at a house under her father’s name. She received monthly governmental aid of 510,000 won ($460). 

By Lim Jeong-yeo (kaylalim@heraldcorp.com)