NSA spied far more on ordinary internet users than on targets

The National Security Agency, the US surveillance authority, has spied on far more ordinary American and overseas internet users than individuals targeted in its investigations, according to a US newspaper.

The Washington Post revealed details of tens of thousands of online conversations intercepted by the NSA – leaked to the newspaper by former intelligence contractor Edward Snowden – in a report that raises further questions about whether the secret eavesdropping by the US infringes individual privacy rights in the name of national security.

The Post found that nine of every 10 email or online message account holders were not the intended targets of surveillance inquiries but were caught up in the NSA's sweeping electronic eavesdropping.

Reviewing 160,000 intercepted conversations between 2009 and 2012 the newspaper found more than 900 email accounts that could be linked to American users. This was despite the NSA trying to hide more than 65,000 names, email addresses or other details to protect the privacy of the Americans in data obtained under powers granted by the US Congress.

The report marks the first time that Mr Snowden, who has temporary asylum in Russia and is wanted by US prosecutors over his leaking, has disclosed communications intercepted by the NSA.

The cache of communications yielded information of value: it led to the capture of Pakistan-based bomb builder Muhammad Tahir Shahzad in 2011 and Umar Patek, a suspect in the 2002 bombings in the Indonesia tourist resort of Bali that killed 202 people.

The newspaper chose not to publish details of other valuable information in case they interfered with ongoing operations, referring obliquely to “a secret overseas nuclear project, double-dealing by an ostensible ally, a military calamity that befell an unfriendly power, and the identities of aggressive intruders into US computer networks.”

The intercepted communications show that the daily lives of more than 10,000 account holders, who were not the target of investigations, were nonetheless recorded by the agency.

The conversations tell “stories of love and heartbreak, illicit sexual liaisons, mental-health crises, political and religious conversions, financial anxieties and disappointed hopes”, the paper reported.