A 24-year-old mother in Tsubame, Niigata Prefecture, has been arrested on suspicion of killing her 3-year-old daughter by throwing her into a river.

Ayumi Sato, an office worker, allegedly dropped her daughter, Miyu, from a bridge in Tsubame on Wednesday night. She has admitted to the charges, the police said.

Sato went to a hospital Thursday morning where her daughter had an appointment and told a staff member that the girl "had disappeared," the police said.

The hospital notified the police, who started a search of the area. They found the girl's body floating in the river at around 3 p.m. Thursday

Sato subsequently admitted she threw the girl from a bridge, the police said. The body was found about 1 km downstream from the bridge.