The Myotsuji temple sits in Aisai, a little known city in the Japanese prefecture of Aichi.

Located more than 9,000km (5,600 miles) from her home in Sri Lanka's Kadawatha district, it is the final resting place of Ratnayake Liyanage Wishma Sandamali.

Wishma died on 6 March 2021 at an immigration detention centre in Nagoya, Aichi's capital. She had been detained there for seven months after overstaying her student visa, and requesting refugee status.

“Even in our dreams, we see our sister,” 30-year old Wayomi Ratnayake told the BBC. “She was only 33 when she died. She could have lived for many more years.”

Wishma was the 18th foreigner to die in Japanese immigration detention since 2007, according to media reports. The country has one of the lowest refugee acceptance rates in the world and her death has increased pressure on officials to reform how people held in such centres are treated.

She lost 20kg (44 pounds) in detention due to a stress-induced stomach condition. According to activists who visited her, her health continued to deteriorate from extreme stress. In her final days, Wishma was vomiting blood.

She repeatedly asked to be taken to hospital and granted provisional release, but these requests were denied.

An investigative report by the Immigration Services Agency of Japan in August 2021 concluded that staff at the detention centre showed a lack of awareness of human rights, and had failed to share details of her illness. It added that some detention officers thought the detainees were faking illness in order to obtain provisional release.

However, prosecutors declined to bring charges against 13 officers at the Nagoya facility over her death. An independent judicial panel later ruled that this decision was unjust.

Led by Wishma's sisters Wayomi and Poornima, 28, the Ratnayake family is suing the Japanese government for damages, alleging it failed to provide Wishma with proper food and healthcare. The case has been ongoing since March 2022.

“If she had got the right medication, she would not have died,” said Wayomi. “We want justice for our sister. The Japanese government is responsible for what happened to her.”

There are some 295 hours of CCTV footage of Wishma, taken at the Nagoya facility in the days leading up to her death.

Five hours of that footage has been presented to a Nagoya court as evidence. The family's lawyers released some of it to the public in April.

In clips shown to the BBC by the family's lawyers, a frail looking Wishma is covered by a blanket as she lies in bed and converses with facility staff. “I can't drink anything,” she says. “I can't breathe. I'm going to die.”

Japanese media also reported that on 23 February, Wishma is seen repeatedly asking to be taken to hospital after vomiting: “I'm going to die today.” A guard responds: “Don't worry, I would be troubled if you died. Let's think of something else.”

On the day of her death, two staff members are seen attempting to revive Wishma. “I think her fingertips feel kind of cold,” says one. Another yells: “Ms Sandamali! Can you hear me?”

It was harrowing viewing for Poornima, who was allowed to watch some of the clips in court, but could not bear to do so continuously. "She should have been in a hospital. The people in the detention centre did not care for her.”

Wayomi added: "There should be a change in the Japanese system so that inmates in the detention centre are protected.”

Wishma's death sparked an uproar in Japan, forcing the government to scrap a controversial immigration bill.

But more than two years later, the proposed amendments to the Immigration Control and Refugee Recognition Act were passed in the lower house of parliament and will come into effect next year. It permits the deportation of those who repeatedly apply for refugee status.

According to official data, only 202 out of 3,772 applicants were recognised as refugees by Japan last year.

Teppei Kasai of Human Rights Watch told the BBC: “If the Japanese government had taken concrete steps to end the indefinite detention of migrants and asylum seekers, [the] deaths [of foreigners in detention], including Wishma Sandamali's, might have been prevented.”

He earlier noted that Japan's immigration and refugee policy has long been mired in red tape and “unnecessarily restrictive measures. Some refugee applicants are held for prolonged periods in detention centres without judicial oversight, sometimes without adequate access to medical services, he added.

A love of all things Japanese

Wishma arrived in Japan in June 2017 on a 15-month student visa, attending a Japanese language school in Chiba prefecture.

A fan of Japanese drama series like Oshin, the English teacher loved Japanese culture and wanted to live in Japan, recalled Wayomi. “She was very innocent and sensitive. She was like a mother to us, very caring and considerate.”

Poornima, who was closest to Wishma, fondly recalled her eldest sister. “We would cook together, and we liked to dance.”

The sisters spoke over the phone on a daily basis, sometimes twice a day. Wishma later moved in with her Sri Lankan boyfriend, whom she met in Japan.

According to the investigative report commissioned by authorities, Wishma stopped attending classes in May 2018 and was expelled by her school the following month.

She started working at a factory in Shizuoka thereafter and applied for refugee status in September. Her application was denied in January 2019.

The following August, she turned herself in to police, alleging domestic abuse. However, she was arrested for overstaying her visa and detained in Nagoya.

Wishma initially wanted to return to Sri Lanka but was unable to get a flight due to Covid curbs. Having changed her mind in December 2020, she remained in detention.

She began suffering from ill health from January 2021, said the report, and her condition began deteriorating the following month.

'We thought it was a mistake'

But all of this was unknown to the Ratnayakes. Their mother last spoke to Wishma sometime in mid-2018, where she told them not to worry if she didn't contact the family.

Wayomi received a text from Wishma in October 2019, congratulating her on her wedding. Subsequent attempts to contact her were unsuccessful.

Then on 8 March 2021, the family was informed by Sri Lankan police of Wishma's death. "We were so shocked. There are no words to describe our grief,” said Wayomi.

When the siblings went to Japan in May to identify their sister's body, they could not recognise her. “When we saw Wishma, her face looked like our grandmother's,” recalled Wayomi. "She had lost so much weight.”

It was the first time they had seen her in two and a half years. They were unable to bring Wishma's body home, due to Covid restrictions as well as the prohibitive cost.

So she was cremated in Nagoya. The sisters attended the funeral, but their mother did not. "She was not mentally fit to see Wishma's body,” said Wayomi.

The siblings gave up their jobs in Sri Lanka - Wayomi was a cashier, Poornima a nursery teacher - in order to pursue their case. They are currently staying at a friend's apartment in Japan. Their living expenses, as well as the lawsuit, is being funded by donations from Japanese citizens.

But not everyone has been sympathetic. In May, lawmaker Mizuho Umemura was suspended by her own party after suggesting in parliament that Wishma's death may have been caused by a hunger strike instigated by activists.

In Sri Lanka, Wishma's case has been widely discussed, with clips of the CCTV footage being circulated online. Opposition and other figures have also urged the government to take up the issue with Japan.

But Sunday Observer editor Pramod de Silva, who heads the largest English newspaper in the country, told the BBC that he does not think the case has affected Sri Lankans' “overwhelmingly positive” views of Japan.

Japan is one of Sri Lanka's biggest aid donors and investors, and Mr de Silva reckoned that Japan is likely to grant a “substantial quota” for Sri Lanka as it opens its doors to foreign labour and foreign migrants

For Wishma's sisters, the fight goes on. “We will not give this up. We will fight this till the end.” (BBC)

•Wishma Sandamali's sisters say they will pursue the case to the end

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