Hong Kong police arrested a 20-year-old mother for negligence on Thursday after she called the police when she found her three-month-old daughter unconscious.

The baby girl, who was later certified as dead, was believed to have been left on her own for more than a day in a village house near the Lok Ma Chau immigration control point after her parents had quarreled.

She was found face down in bed by her mother when she ­returned home shortly after mid-day on Thursday.

“The baby girl was certified dead by paramedics at the scene,” a police spokesman told the South China Morning Post, adding that there were no injury marks found on the body.

An autopsy will be carried out to ascertain the baby’s cause of death.

The mother is now in custody as police search for the girl’s 40-year-old father. According to a police source, he had been at home with the baby but had left by the time his wife returned.