Eric Holder (AP Photo) Eric Holder (AP Photo)

Attorney General Eric Holder can't say how many times the Justice Department has seized journalists' records during his tenure.

"I'm not sure how many of those cases that I have actually signed off on," Holder told NPR.  "I take them very seriously. I know that I have refused to sign a few, pushed a few back for modifications."

Holder said Tuesday that he was unaware that a DOJ leak investigation involved secretly acquiring telephone records of Associated Press journalists because he had recused himself from that probe.

In a letter to Holder and his deputy Tuesday, The Washington Post and more than 50 other news organizations (including NPR) rejected “an overreaching dragnet for newsgathering materials." The media coalition demanded that the AP records be destroyed and that the DOJ "announce whether it has served any other pending news media-related subpoenas that have not yet been disclosed."