LONDON (AFP) - British undercover journalist Mazher Mahmood, known for his "Fake Sheikh" disguise and a string of celebrity tabloid stings, was found guilty on Wednesday (Oct 5) of perverting the course of justice.

Mahmood, who conceals his identity after a series of alleged death threats, is famous for his front-page scoops in which he poses as a wealthy figure from the Gulf and encourages celebrities into making embarrassing revelations.

Mahmood, 53, and his driver Alan Smith, 66, were convicted of conspiring to pervert the course of justice following a trial at England's Old Bailey central criminal court in London.

A jury found they plotted to suppress evidence in the collapsed 2014 drugs trial of British pop singer and TV star Tulisa Contostavlos, which resulted from a Mahmood sting.

In a typically elaborate operation, Mahmood posed as a film producer and offered Contostavlos a Hollywood career and a movie role alongside star Leonardo DiCaprio.

She was accused of arranging for Mahmood, who dubbed himself "King of the Sting", to be sold cocaine by one of her contacts.

In a statement to police, Smith said the singer had made anti-drugs comments in the car - which could have proved helpful to her lawyers in the case.

Smith e-mailed Mahmood the statement and spoke to the reporter, after which Smith removed the comments from his statement.

As this emerged, the Contostavlos trial collapsed and prosecutors turned their attention to Mahmood and Smith.

The pair will be sentenced on October 21.

Mahmood's list of sting targets include several members of the royal family, sports stars and TV celebrities.

British prosecutors have since dropped a number of live criminal cases in which Mahmood was due to be a witness and announced a review of 25 past convictions.

The Criminal Cases Review Commission is currently reviewing six cases involving celebrities who were convicted following involvement with Mahmood.