Washington (CNN) Agents from Immigration and Customs Enforcement and the FBI are utilizing state driver's license databases to scan through "millions of Americans' photos without their knowledge or consent," The Washington Post reported Sunday.

A cache of internal documents and emails from ICE and the FBI obtained by Georgetown Law's Center on Privacy and Technology and provided to the paper show "federal investigators have turned state Department of Motor Vehicles databases into the bedrock of an unprecedented surveillance infrastructure," the Post said.

While law enforcement use of DNA and fingerprints taken from criminal suspects in other criminal investigations is standard practice, DMV records hold photos of large numbers of state residents who haven't been charged with a crime, the paper reported.

ICE's reported use of driver's license databases for facial recognition comes amid increased calls from the Trump administration to use immigration raids to identify and prosecute undocumented immigrants. President Donald Trump said last month his administration would launch a series of ICE raids sometime after the Fourth of July, and acting Homeland Security Secretary Kevin McAleenan on Sunday defended the practice, telling ABC "interior enforcement" is part of "balanced enforcement process."

ICE spokesman Matthew Bourke told CNN in a statement Monday the department doesn't comment on investigation techniques, but it has "the ability to collaborate with external local, federal and international agencies to obtain information that may assist in case completion and subsequent prosecution."

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