Tokyo immigration authorities prevented a Turkish detainee from seeing a doctor for nearly a day despite him suffering acute abdominal pain that was later diagnosed as appendicitis and peritonitis, his supporters said Monday.

Doctors said the man could have died if the peritonitis had further progressed to sepsis and warned against letting detention officials make medical decisions.

The 29-year-old man developed symptoms and asked for medical assistance on June 3 last year, but officials at the Tokyo Regional Immigration Bureau just took him to a separate room and said they would "monitor" his condition.