Western governments are believed to be behind a highly malicious software application that can be used to spy on a person's emails and phone calls and even recreate a target's deleted computer files.
The Regin virus was researched by anti virus software makers Symantec Corp who said they were aware of about 100 cases of people being targeted by what they believe is a 'government surveillance tool'.
Gavin O'Gorman, a principal intelligence analyst at Symantec, said: "We would estimate it is created by and used by a western government based on the type of victims and the complexity of the malware."
He added: "It has a number of different stages and is like a Russian doll essentially."
Regin works by gaining access to a target's computer then accessing files and decrypting user data in stages. It is capable of stealing user names and passwords, recovering deleted files from a computer's memory and it can even access mobile phone providers routers and search for specific phone calls to monitor.
Mr O'Gorman said based on the sophistication of the virus it must have been developed by a professional level of programmers and appears to be designed for a very specific type of surveillance aimed at carefully selected targets.
The security expert added that it is not thought the general public will be targeted by the virus as it is a targeted surveillance tool not a mass surveillance tool.
So far the virus' main targets that have been recorded have been people based in the telecommunications, energy, airline, hospitality and research sectors and a large proportion of them have been located in Russia and Saudi Arabia.