US intelligence officials had prior knowledge of British intelligence's efforts to destroy hard drives containing leaked information from the National Security Agency, according to redacted emails and other documents obtained by the Associated Press from the NSA under the Freedom of Information Act.

On July 19, 2013, The Guardian editor Alan Rusbridger agreed to destroy hard drives containing copies of some of the secret files leaked by Edward Snowden. The decision was taken after the UK newspaper was threatened with police raid and prosecution under the UK's Official Secrets Act.

The documents obtained by the AP reveal that Richard Ledgett, then director of NSA's Threat Operations Center and a member of NSA's Media Leaks Task Force, sent an email to then National Security Agency director General Keith Alexander within hours of Rusbridger's consent to the destruction.

"Good news, at least on this front", Ledgett wrote in an email titled "Guardian data being destroyed". Alexander forwarded this to the Director of National Intelligence James Clapper with the message, "Jim- Here is the report I got".

The following day, a senior editor and a Guardian computer expert used angle grinders and other tools to pulverize the hard drives and memory chips on which the encrypted files had been stored. A few hours after the destruction, Alexander verbally briefed Clapper about the development, who then sent a thank you email as a reply to the original email thread.

It's unclear from the documents whether the NSA was involved in ordering the data destruction, or whether the US pressured Britain to compel the newspaper to return the files. After the forced destruction came into light, the Obama administration pretended that it knew nothing about the incident.

"I've seen the published reports of those accusations, but I don't have any information for you on that... The only thing I know about this are the public reports about this", said press secretary Josh Earnest during a White House press briefing, a month after the incident.

The White House said Thursday the comment from Ledgett was confined to intelligence operations because it was "good news" that classified information was recovered and "didn't reflect a broader administration view" on press freedoms.