The American Civil Liberties Union (ACLU) announced Tuesday that it has filed a federal lawsuit against key members of President Obama’s national security team over the National Security Agency’s telephone surveillance, the first legal challenge to the newly disclosed intelligence gathering system, The Los Angeles Times reports.

The suit argues that the NSA’s ongoing, daily collection of Verizon telephone records is unconstitutional and should be stopped.

"This dragnet program is surely one of the largest surveillance efforts ever launched by a democratic government against its own citizens," Jameel Jaffer, ACLU deputy legal director, said in a statement, repeated in the article. "It is the equivalent of requiring every American to file a daily report with the government of every location they visited, every person they talked to on the phone, the time of each call, and the length of every conversation.”

As a Verizon customer, the ACLU claims that the NSA’s seizure of telephone records “compromises sensitive information about its work” and harms its ability to freely communicate.