The Committee to Protect Journalists will release a report on U.S. press freedom Oct. 10. Leonard Downie Jr., a former Washington Post executive editor and current Arizona State University professor, has written an article based on the report for the Post.

After the New York Times published a 2012 story by David E. Sanger about covert cyberattacks by the United States and Israel against Iran’s nuclear enrichment facilities, federal prosecutors and the FBI questioned scores of officials throughout the government who were identified in computer analyses of phone, text and e-mail records as having contact with Sanger.

“A memo went out from the chief of staff a year ago to White House employees and the intelligence agencies that told people to freeze and retain any e-mail, and presumably phone logs, of communications with me,” Sanger said. As a result, longtime sources no longer talk to him. “They tell me: ‘David, I love you, but don’t e-mail me. Let’s don’t chat until this blows over.’ ”

Sanger, who has worked for the Times in Washington for two decades, said, “This is most closed, control-freak administration I’ve ever covered.”