Edward J. Snowden, the former National Security Agency (NSA) contractor who leaked a trove of documents revealing the agency’s surveillance operations, said he raised his concerns to more than 10 officials, “none of whom took any action to address them,” before he decided to give the documents to journalists.

Mr. Snowden’s comments, in written answers to questions by members of the European Parliament that were released on Friday, amplified previous assertions that he initially tried to raise concerns internally about surveillance collection he believed went too far.

An NSA spokeswoman declined to comment, but the agency has previously said its internal investigation, including interviews with co-workers, found no evidence that he had brought concerns to the attention of anyone.

But in his written testimony, Mr. Snowden insisted that he had, adding that his efforts had elicited two types of responses. Some people, he said, responded with “well-meaning but hushed warnings not to ‘rock the boat’” for fear of retaliation like being investigated by the FBI.

“Everyone in the intelligence community is aware of what happens to people who report concerns about unlawful but authorised operations,” he wrote.

Other people, he said, told him to “let the issue be someone else’s problem.”

The Justice Department has charged Mr. Snowden with violating the Espionage Act. He is living in asylum in Russia.

In his testimony, Mr. Snowden said he has “no relationship” with the governments of Russia or China, but he acknowledged that he was approached by Russian intelligence officers when he arrived in Moscow. He reiterated his previous claims that he took no documents with him to Russia after turning over archives to several journalists in Hong Kong.

No protection in U.S.

He said that he did not want to stay in Russia but that his efforts to obtain asylum in various countries in Europe had not succeeded, and he blamed U.S. diplomatic pressure.

Mr. Snowden also took issue with the contention by some officials that whistleblower laws would have protected him if he had gone through official channels. President Barack Obama, for example, has pointed to an executive order he issued that extended protections against retaliation to employees of intelligence agencies.But Mr. Snowden noted that Mr. Obama’s directive covers only intelligence agency employees, not outside contractors, so “individuals like me were left with no proper channels.”

On Monday, Mr. Snowden is scheduled to appear in a live video feed from Russia at the South by Southwest conference in Austin, Texas, to discuss communications privacy issues. — New York Times News Service

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