WASHINGTON -- The U.S. Director of National Intelligence James Clapper on Thursday defended the code-named PRISM program that tapped into internet companies for intelligence, saying the related reports published by the British Guardian newspaper and the Washington Post contained "numerous inaccuracies."

Clapper said in a statement that the articles omitted key information regarding how a classified intelligence collection program is used to prevent terrorist attacks and the numerous safeguards that protect privacy and civil liberties.

Clapper also warned that the unauthorized disclosure of information about this important program was "reprehensible" and risked important protections for the security of Americans.

According to the reports posted by the Guardian and the Washington Post, U.S. National Security Agency (NSA) and the FBI are secretly tapping directly into the central servers of nine U.S. internet companies, extracting audio, video, photographs, e-mails, documents and connection logs that enable analysts to track a person's movements and contacts over time.

This code-named PRISM program was established in 2007 and saw exponential growth in the past 6 years. Microsoft, Yahoo, Google, Facebook, PalTalk, AOL, Skype, YouTube and Apple all participated knowingly in PRISM operations, the reports said.

Clapper said that discussing programs like this publicly would have an impact on the behavior of the agency's "adversaries" and make it more difficult to understand their intentions.

"Surveillance programs like this one are consistently subject to safeguards that are designed to strike the appropriate balance between national security interests and civil liberties and privacy concerns," argued Clapper.