The family of a Sri Lankan woman who died in 2021 while detained at a Japan immigration center on Wednesday urged prosecutors who had previously dropped the case to indict officials on charges of professional negligence resulting in death.

The family of Ratnayake Liyanage Wishma Sandamali made the appeal following a December ruling by an independent judicial committee that found the prosecutors' decision was "unjust," paving the way for the case to be reinvestigated.

Wishma arrived in Japan in 2017 as a student but was later taken into custody at a Nagoya Regional Immigration Services Bureau facility for overstaying her visa. She died at the age of 33 in March 2021 after complaining of ill health, which included vomiting and stomach pain, for around a month.

"I told the prosecutors to conduct a fair investigation and to indict (the officials) on charges of professional negligence resulting in death, so that this will never happen again," Wayomi, Wishma's sister, told reporters after submitting the request to Nagoya District Public Prosecutors Office.

Sisters of dead detainee Ratnayake Liyanage Wishma Sandamali, Wayomi (far R) and Poornima (2nd from R), head to the building of Nagoya District Public Prosecutors Office in Nagoya on July 12, 2023. (Kyodo)

The document presented to prosecutors said immigration center officials "had a duty to prevent" her death, as Wishma would not have died had she received proper medical care.

It also said they had "a duty to foresee" there was a possibility Wishma could die if she was not provided medical care.

In June last year, prosecutors dropped charges against 13 immigration bureau officials, deciding they need not face charges over allegations of murder and abandonment resulting in death after a criminal complaint filed by the family.

But citizens who form the committee for the inquest of prosecution in Nagoya said the prosecutors should reconsider whether they can charge officials at the immigration bureau, including the director at the time, for professional negligence resulting in her death.

As for the murder and abandonment allegations, the committee determined it was "difficult" to say that the prosecutors' investigations were insufficient.

Wishma's death sparked scrutiny of Japan's treatment of foreign detainees and triggered calls demanding more information about Wishma's death. The government was forced a few months later to drop a bill revising rules on foreigners facing deportation, including asylum seekers.

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