April 6, 2026Updated April 7, 2026, 1:55 p.m. ET(This story was updated to add new information.)A Vietnamese national died in immigration detention at the Miami Correctional Facility last week, according to a news release from U.S. Immigration and Customs Enforcement.Tuan Van Bui, 55, was pronounced dead at 6:10 p.m. on April 1 after staff found him unresponsive. Despite medics' intervention, he could not be resuscitated. Bui's cause of death is under investigation.Bui legally entered the US in 1990 under the Amerasian Homecoming Act, which granted visas to children born in Vietnam to American fathers and their immediate next-of-kin. ICE's news release said that Bui never received or applied for American citizenship. His AM-1 visa could have qualified him for lawful permanent residency, often known as a 'green card.'When asked if Bui had ever applied for or received any type of legal status other than citizenship, ICE referred IndyStar to US Citizenship and Immigration Services, who did not immediately respond to a request for comment.Bui was ordered removed from the country by an immigration judge in 2005. He had "multiple convictions" at the time of his death, according to the ICE release. It's unclear, however, if that's what led to the removal order.Federal court records show that at the time of his death, Bui was challenging his detention through a habeas corpus case.Centurion, the company that provides medical care for detainees and inmates housed at the prison, did not immediately respond to a request for comment.Bui is the second immigration detainee to die in the facility since ICE began using it in October 2025. Lorth Sim, a 59-year-old man from Cambodia, died on Feb. 16. The Miami County Coroner ruled that Sim died of natural causes from a combination of cardiovascular disease and diabetes.The Indiana Department of Correction directed inquiries to ICE.Ryan Murphy is the communities reporter for IndyStar. She can be reached at rhmurphy@indystar.com.