The man who acknowledged leaking details of classified U.S. surveillance programs seemed to melt into the streets of Hong Kong as FBI investigators worked Tuesday to build a case against him and criticism of the programs continued to mount.
Edward Snowden, 29, apparently checked out of his Hong Kong hotel room Monday and has not been seen since. A reporter who helped develop stories from the information Snowden leaked said he believes the former contractor for the National Security Agency remains there.
U.S. authorities are preparing charges against Snowden, a law enforcement source told CNN on Tuesday. But they are not imminent, the source said.
As authorities investigated, one U.S. congressman told CNN that journalists who published the leaked information should be punished.
And the first civil lawsuits were filed against federal officials, arguing that the surveillance programs are unconstitutional.
Snowden, a former computer security contractor, acknowledged in a Guardian newspaper interview that he gave journalists classified documents about U.S. surveillance of telephone and Internet traffic.
The FBI has been investigating the leaks, but it was unclear Tuesday how far along the agency was.
Snowden told the Guardian that he expects to be charged under the Espionage Act and said he traveled to Hong Kong in hopes that state's commitment to free speech would prevent his extradition to the United States.
Will journalists face prosecution?
On Tuesday, one lawmaker told CNN's AC360 that journalists tied to the leaks should also be prosecuted.
"If they willingly knew that this was classified information, I think actions should be taken, especially on something of this magnitude," said Rep. Peter King, a New York Republican who leads the House Homeland Security subcommittee on Counterintelligence and Terrorism.
"There is an obligation both moral, but also legal, I believe, against a reporter disclosing something which would so severely compromise national security," he said. "As a practical matter, I guess there have been in the past several years a number of reporters who have been prosecuted under (the Espionage Act)."
As for Snowden, King said there's no doubt he should face charges.
"I think what he's done has been incredible damage to our country. It's going to put American lives at risk," he said.
The congressman did not provide specific examples of how the leaked information damages national security, but argued that it helps enemies of the United States.
"Al Qaeda and its allies now know with great exactitude exactly what we're doing," he said, "and how we're doing it."
Snowden's disclosures have fueled new debate about the U.S. government's collection of records of domestic telephone calls and overseas Internet activity in the global hunt for terrorists and criminals.
Civil liberties advocates say the measures are unacceptable intrusions. But supporters say they are legal and have yielded evidence that has helped stop terror plots.
White House spokesman Jay Carney said Tuesday that the measures "strike a balance between our security interest and our desire for privacy."
"There has to be some modest concession to the need for information as we pursue terrorists who mean to do harm to the country and take the lives of Americans," Carney said. "But ... we need to make sure that the programs we have in place are properly overseen, that they are legal, that they are authorized by Congress and they are authorized by the courts, and that is the case here."
But at least two civil lawsuits have been filed so far against federal officials, arguing that the collection of phone records is unconstitutional and calling for a judge to block the measure.
"The practice is akin to snatching every American's address book -- with annotations detailing whom we spoke to, when we talked, for how long, and from where," the American Civil Liberties Union and several other groups said in a federal lawsuit filed Tuesday. "It gives the government a comprehensive record of our associations and public movements, revealing a wealth of detail about our familial, political, professional, religious and intimate associations."
A Philadelphia couple who allege they were singled out for electronic surveillance because of their criticism of the U.S. military filed a $3 billion class-action lawsuit, claiming their privacy and free speech rights were compromised.
The Justice Department declined to comment on the lawsuits.