A 31-year-old woman in Niigata Prefecture was arrested Wednesday on suspicion of killing her 3-month-old daughter by repeatedly dropping her on the floor, police said.
Noriko Ito, a Nagaoka city official in charge of promoting gender equality, admitted the allegation to police after her daughter, Hikari, was confirmed dead in hospital from brain contusion.
People close to her said she appeared distressed over child-rearing, according to investigative sources. Married to a fellow Nagaoka city official, Ito also has a son and was on childcare leave from April, according to the city.
She was home alone with the newborn at the time of the incident. The case came to light when the baby's grandmother called an ambulance after finding her bleeding on the floor when she visited their home on Wednesday.
Ito accompanied Hikari when she was taken to hospital and appeared panic stricken, according to police and medical staff.
Police, who searched the home Thursday, said Hikari had no wounds to make them suspect Ito had previously abused the child.