Supporters of inmates held at the Nishi-Nihon Japan Immigration Center said a hunger strike in March has led to more provisional releases for those with health problems.
But immigration center officials denied any connection between the hunger strike and the provisional releases.
About 70 male inmates began a hunger strike March 8, demanding that those with serious health problems be given provisional releases to receive medical care.
A citizens group aiding the inmates said that after the hunger strike, a Pakistani man whose weight had plummeted due to depression and fever was granted a provisional release.
Another Pakistani man taken to a hospital in December after falling unconscious from extremely high blood pressure was also told he would be given a provisional release.
The two had been confined at the immigration center for over a year. The support group had been requesting a provisional release for them since late last year because of their failing health. The request was initially rejected in February.