The U.S. Government Accountability Office and the Health and Human Services inspector general have both opened reviews into the Trump administration’s handling of migrant children separated from their families at the border, Politico reports. The GAO intends to focus on the processes used to track the whereabouts of children after they were separated—a process that immigration advocacy groups have said is nonexistent. The HHS inspector general will reportedly scrutinize the health and safety precautions taken for children being held in the agency’s shelters. President Trump signed an executive order last week calling for an end to family separations amid mounting public outrage over the policy, but critics say that has done nothing to reunite hundreds of migrant children already in shelters with their parents. Several hundred undocumented migrant parents are believed to already have been deported from the U.S. without their children.