Intensive care nurses immediately doubted the word of federal immigration officers when they arrived at a Minneapolis hospital with a Mexican immigrant who had broken bones in his face and skull.

Immigration and Customs Enforcement agents initially claimed Alberto Castañeda Mondragón had tried to flee while handcuffed and “purposefully ran headfirst into a brick wall,” according to court documents filed by a lawyer seeking his release.

But staff members at Hennepin County Medical Center determined that could not possibly account for the fractures and bleeding throughout the 31-year-old’s brain, said three nurses familiar with the case.