EL PASO, Texas — The federal agency tasked with overseeing security at transportation hubs has been violating its own policy by allowing migrants who have been released from federal custody onto flights despite not having required documents, according to several Department of Homeland Security officials.

For the past six months, the Transportation Security Administration has allowed migrants released from the custody of other Homeland Security agencies to board flights to other parts of the country despite the passengers lacking any of the 15 documents it states are the only acceptable forms of identification.