By Mark Hosenball and Patricia Zengerle
WASHINGTON (Reuters) - The top U.S. intelligence official called on Wednesday for Edward Snowden and journalists who obtained documents the former contractor took without authorization from the National Security Agency to return the materials to authorities.
At a hearing where the heads of five U.S. intelligence agencies ratcheted up rhetoric calling Snowden a "grave threat" to the nation, U.S. Director of National Intelligence James Clapper made comments that appeared to accuse journalists who wrote stories based on Snowden's leaks.
"Snowden claims he's won and that his mission is accomplished," Clapper testified at the U.S. Senate Intelligence Committee's annual hearing on global security threats.
"If that is so, I call on him and his accomplices to facilitate the return of the remaining stolen documents that have not yet been exposed to prevent even more danger to U.S. security," he said.
Clapper's comments were immediately criticized by Glenn Greenwald, a writer who met with Snowden in Hong Kong and wrote about documents he received from him in the Guardian and other media outlets. Greenwald currently is setting up a new media venture with EBay founder Pierre Omidyar.
"Is it now the official view of the Obama administration that these journalists and media outlets are 'accomplices' in what they regard as Snowden's crimes? If so, that is a rather stunning and extremist statement. Is there any other possible interpretation of Clapper's remarks?" Greenwald wrote on a personal blog.
Snowden, who has accepted temporary asylum in Russia, has said that he gave journalists all the documents he took with him when he left his job as an NSA contractor in Hawaii.
One U.S. official familiar with the matter said privately this week that in reality, U.S. authorities do not know how many documents Snowden downloaded.
Some U.S. officials have suggested publicly that he acquired as many as 1.7 million documents, though several sources familiar with what he delivered to media outlets said the quantity was a fraction of that - at most hundreds of thousands of papers.
In the wake of Snowden's disclosures and deep public concern about widespread surveillance, President Barack Obama has proposed NSA eavesdropping reforms, including restrictions on a current agency program that collects masses of telephone "metadata" on both foreigners and Americans.
Several bills calling for reforms of the NSA's data collection are making their way through Congress.
There is strong support for Snowden around the world.
On Wednesday, a Norwegian member of parliament nominated the former contractor for the 2014 Nobel peace prize.
(Editing by Dan Grebler)