48-year-old Nigerian, Elizabeth Aruoriwo Obueza is currently fighting for her release from solitary confinement in Tokyo, Japan. Her crime? Being an activist for detained foreigners in Japan.

As reported by Reuters, Obueza fled Nigeria for Japan in 1991 to escape female genital mutilation and applied for asylum in 2011, but her application was rejected. And two weeks ago, after authorities turned down an appeal against her asylum rejection, the 48-year old was arrested and kept in solitary.

Shoichi Ibusuki, an immigration lawyer fighting for Obueza’s release, said the Nigerian was targeted and detained for being an activist. A statement echoed by Mitsuru Miyasako, the head of the Provisional Release Association in Japan, “Elizabeth is held in solitary because she’s an activist and immigration officials don’t want her causing trouble,” she said. However, Miyasako is more concerned about the psychological effects of being in solitary. “Locking someone up alone in a tiny room is to ruin them psychologically.”

In September 2015, Japans’ Ministry of Justice embarked on a mission to cut down on the number of immigrants living in the country without visas, about 60,000 of them. Many of these foreigners have been arrested and detained, while others live restricted lives under “provisional release”, barred from working and traveling freely. For over a decade, Obueza has dedicated her life to these immigrants and campaigning for asylum seekers by visiting immigration detention centers across Japan, and assisting detainees in getting legal help.

Being locked up is not strange to the 48-year-old woman who was detained for 10 months in 2011. Speaking to Reuters from across a security divide at the detention center where she’s held, Obueza said, “I want to help people. Give me the right to help people – don’t put me in here.”

Besides the fact that she is being unfairly detained, Obueza is also being treated unfairly; where other detainees are typically locked up for 18 hours a day, she is being locked up for more than 22 hours, almost an entire day. But even isolation has not stopped Obueza from being an activist as she continues her job of helping detainees within the small window of time and space given her. “When I go outside my room, I go around the windows and talk to the others. I advise them,” she said.

According to Miyasako, Obueza has helped hundreds of immigrants, and it annoys immigration authorities. Activists and lawyers say people like Obueza, many of whom are on provisional release and have lived in Japan for decades, have been among those targeted by the authorities. And notwithstanding the fact that they are legally restricted from working, these immigrants contribute a lot to Japan’s construction and manufacturing sectors.