A adult female in Tokyo was found frozen to death after her parents held her captive in a tiny room for 15 years — and she weighed only 42 pounds when she died at age 32, according to police.

According to Reuters, Airi Kakimoto’s parents reported her death to Western Japan’s Osaka Prefectural Police Departmen on Saturday, five days after they discovered she had died.

Police told Reuters that Kakimoto was extremely malnourished at the time of her death, weighing only 42 pounds at a height of 4.76 feet tall.

Kakimoto’s parents reportedly told police that their daughter was mentally ill, and that they kept her confined to a single room beginning when she was a teenager because she had begun to exhibit violent tendencies.

The 32-square-foot room was reportedly built as an addition to the family’s single story home, and had a double door on it that could only be unlocked from the outside. The room had a makeshift toilet and a water tank just outside, and the parents installed surveillance cameras at the home, which was surrounded by a fence.

The parents reportedly admitted to feeding their daughter only once a day, and explained the delay in reporting their daughter’s death by claiming that “We wanted to be together with our daughter.”

They have been charged with illegally disposing of a body, and the Reuters report suggests that additional charges are expected.

This is a developing story and will be updated as more information becomes available.