An Afghan national who fought alongside U.S. forces died from an allergic reaction while in the custody of Immigration and Customs Enforcement, one day after he was detained for deportation proceedings, his death certificate shows.Mohammad Nazeer Paktiawal, 41, suffered “an adverse drug reaction” to an unidentified substance, which triggered anaphylaxis and exacerbated his asthma, according to the document. His March 14 death at a Dallas hospital was ruled to be an accident.Paktiawal’s sudden death in ICE custody has drawn outrage because he had risked his life fighting as an ally of U.S. Special Forces in Afghanistan for a decade. Members of Congress and an advocacy group, AfghanEvac, have demanded answers about what happened.Out of more than 50 ICE detention deaths during President Donald Trump’s second term, Paktiawal’s is the first to be ruled an accident, according to tracking by The Associated Press. Most of the others have been blamed on natural causes or suicide.

On Monday, AfghanEvac called on Texas authorities to release his full autopsy report, which they have sought to withhold by arguing its disclosure would interfere with an ongoing criminal investigation into the death.