SEATTLE » Senate Judiciary Chairman Patrick Leahy and The Associated Press sent separate letters to U.S. Attorney General Eric Holder on Thursday expressing concerns that the FBI faked an AP story to catch a bomb threat suspect in 2007. The AP also asked the Justice Department to account for other times it has posed as a media organization in an investigation.

"When law enforcement appropriates the identity of legitimate media institutions, it not only raises questions of copyright and trademark infringement but also potentially undermines the integrity and credibility of an independent press," wrote Leahy, a Vermont Democrat.

Documents obtained by the San Francisco-based Electronic Frontier Foundation and publicized this week by Christopher Soghoian, the principal technologist for the American Civil Liberties Union, revealed that the FBI’s Seattle office forged an AP story to help catch a 15-year-old suspect who had been making bomb threats at a high school near Olympia.

The FBI obtained a warrant from a federal magistrate judge to send a "communication" to a social media account associated with the bomb threats. The "communication," which contained a software tool that could verify Internet addresses, turned out to be a link to a phony AP story about the bomb threats posted on a Web page created by the FBI. The suspect clicked on the link, revealing his computer’s location and Internet address, and helping agents confirm his identity.

In a written statement, Frank Montoya Jr., the FBI’s special agent in charge in Seattle, said the technique is used "in very rare circumstances."

"Every effort we made in this investigation had the goal of preventing a tragic event like what happened at Marysville and Seattle Pacific University," he said, referring to two local school shootings this year.

The AP said in its letter that it is never appropriate for the government to pose as an independent news organization. It requested an accounting of how often the DOJ has done so; sought Holder’s word that the DOJ would never again misrepresent itself as the AP; and asked for policies and guidelines to ensure the DOJ does not further impersonate news organizations.

"The FBI both misappropriated the trusted name of The Associated Press and created a situation where our credibility could have been undermined on a large scale," AP General Counsel Karen Kaiser wrote. "The FBI may have intended this false story as a trap for only one person. However, the individual could easily have reposted this story to social networks, distributing to thousands of people, under our name, what was essentially a piece of government disinformation."

The Justice Department did not immediately respond to requests for comment on the letters.