The Drug Enforcement Administration has been busy implementing a nationwide license plate reader and real-time tracking program, the American Civil Liberties Union said Monday.

The program was designed to fight drug trafficking near the U.S.-Mexico border - to assist in the seizure of cars, money and other drug trafficking assets, reported The Wall Street Journal.

However, the program has been quickly expanded across the nation, and the DEA previously suggested that "other sources" would even be able to contribute data to the database, the ACLU said.

While the documents obtained by the ACLU through a Freedom of Information Act request were heavily redacted and thus their usefulness limited, the group was able to get a clearer picture of the program's expansion.

High-tech cameras located on major highways track vehicles in real-time, collecting information on vehicle movements including location and direction of travel, and many of the cameras are capable of capturing images of drivers and passengers, the WSJ reported.

"If the DEA's collection of location information is as extensive as the agency has suggested in its limited comments to legislatures, the public deserves a more complete and comprehensive explanation than the smattering of records we have obtained can provide," the ACLU said, referencing a 2012 testimony by a DEA agent in which it was revealed that the program began in 2008 and provides access to federal, state and local law enforcement organizations.

The records "offer documentation that this program is a major DEA initiative that has the potential to track our movements around the country," the ACLU continued. "With its jurisdiction and its finances, the federal government is uniquely positioned to create a centralized repository of all drivers' movements across the country - and the DEA seems to be moving toward doing just that. If license plate readers continue to proliferate without restriction and the DEA holds license plate reader data for extended periods of time, the agency will soon possess a detailed and invasive depiction of our lives."

The ACLU notes that privacy concerns are exacerbated if the DEA tracking program is combined with other government spying efforts, such as the bulk cell phone data collection program.

A Justice Department spokesman told Fox News that the tracking program complies with federal law, and includes "protocols that limit who can access the database and all of the license plate information is deleted after 90 days."