Symantec researchers likened the bug to Stuxnet, a computer worm that targeted Iran's nuclear program
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Is Regin 'most sophisticated' computer spying bug?

A leading computer security company says it has discovered one of the most sophisticated pieces of malicious software ever detected.

Symantec says the bug, called Regin, can capture screen shots, direct a mouse, and steal passwords.

It has been used to spy on government organisations, businesses and private individuals since at least 2008.

However Vikram Thakur of Symantec told the BBC's Adnan Nawaz he did not think the bug was used for mass surveillance.

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