The Obama administration is seeking to compel a writer to testify about his confidential sources for a 2006 book about the Central Intelligence Agency, a rare step that was authorized by Attorney General Eric H. Holder Jr. The author, James Risen, who is a reporter for The New York Times, received a subpoena on [April 26] requiring him to provide documents and to testify May 4 before a grand jury in Alexandria, Va., about his sources for a chapter of his book, State of War: The Secret History of the C.I.A. and the Bush Administration. The chapter largely focuses on problems with a covert C.I.A. effort to disrupt alleged Iranian nuclear weapons research. Mr. Risen referred questions to his lawyer, Joel Kurtzberg, ... who said that Mr. Risen would not comply with the demand and would ask a judge to quash the subpoena. He intends to honor his commitment of confidentiality to his source or sources, Mr. Kurtzberg said. We intend to fight this subpoena. The subpoena comes two weeks after the indictment of a former National Security Agency official on charges apparently arising from an investigation into a series of Baltimore Sun articles that exposed technical failings and cost overruns of several agency programs that cost billions of dollars.