Attorney General Michael Mukasey and three other top Bush administration officials are weighing in against legislation that would allow reporters to protect the identities of confidential sources who provide sensitive, sometimes embarrassing information about the government.

The "Free Flow of Information Act" proposed by Sen. Arlen Specter, R-Pa., could harm national security and would encourage more leaks of classified information, the four officials wrote in letters to senators made public Thursday.

The legislation gives an overly broad definition of journalists that "can include those linked to terrorists and criminals," wrote Mukasey and National Intelligence Director Mike McConnell.

"All individuals and entities who 'gather' or 'publish' information about 'matters of public interest' but who are not technically designated terrorist organizations, foreign powers or agents of a foreign power will be entitled to the bill's protections," Mukasey and McConnell stated in their joint letter.

Specter, the top Republican on the Senate Judiciary Committee, responded: "My staff met today with DNI and DoJ officials regarding the concerns expressed in the letter, and we are considering them."

"I think the legislation has an important purpose," Specter added. "I think we can make reasonable accommodations to their concerns, and we're working on it."

In a separate letter, Defense Secretary Robert Gates said the nation would be more vulnerable to "adversaries' counterintelligence efforts to recruit" those shielded by the bill.

Homeland Security Secretary Michael Chertoff said the bill would erect roadblocks to gathering information "from anyone who can claim to be a journalist, including bloggers" and Internet service providers.

The opposition of the top Bush administration officials follows recent high-profile episodes in which reporters have fought efforts to reveal their government sources.

Former USA Today reporter Toni Locy is seeking to reverse a contempt of court citation for refusing to reveal her Justice Department and FBI sources for stories about the criminal investigation of the 2001 anthrax attacks.

Among the government leakers of CIA operative Valerie Plame's identity, it turns out, were President Bush's top political adviser, Karl Rove, and Vice President Dick Cheney's former chief of staff, I. Lewis "Scooter" Libby.

Former New York Times reporter Judith Miller spent 85 days in jail for refusing to identify Libby to investigators.

The leaks of Plame's identity occurred after Plame's husband publicly accused the administration of twisting prewar intelligence to exaggerate the Iraqi threat.

Special Counsel Patrick Fitzgerald eventually won convictions against Libby for perjury, obstruction and lying to the FBI. Bush commuted Libby's 30-month prison sentence.

Co-sponsors on the bill include Senate Judiciary Committee Chairman Patrick Leahy, D-Vt., Democratic Sens. Barbara Boxer of California, Christopher Dodd of Connecticut, Charles Schumer of New York and Tim Johnson of South Dakota, along with Republican Sens. Lindsey Graham of South Carolina and Richard Lugar of Indiana.