Oct. 21: Pakistani origin journalist Mazher Mahmood, 53, known as the "Fake Sheikh", was today sent to prison for 15 months for "perverting the course of justice" in the collapsed drugs trial of pop star Tulisa Contostavlos.

"Your turn now, Mazher," shouted a man, possibly a victim of one of Mazher's over 100 sting operations, from the public gallery. The case is one of the most important in British journalism.

Mazher's driver, Alan Smith, 67, who was persuaded by the journalist to change evidence that would have proved helpful to the pop singer, was given a 12-month prison sentence but he won't need to go to jail if he avoids committing another criminal offence for two years.

With good behaviour, Mazher himself could be out on parole after serving half his sentence but his career as an investigative journalist is now over.

He can count himself unlucky that he has been caught out in a case of entrapment journalism which has become very common in Britain.

But while other could claim their operations were "in the public interest", the judge, Gerald Gordon, said Mazher's subterfuge was intended to enhance his personal reputation.

The plot to show the pop singer was a drug dealer had been devised by Mazher.

"Mazher Mahmood, it was your idea," the judge said. "The motive was to preserve and enhance your reputation. You wanted another scalp and Miss Contostavlos's conviction would have achieved that. And to achieve that, when you saw a problem, you were prepared for the court to be deceived."

Many of those who were convicted as a result of Mazher's journalism are now seeking compensation which one media lawyer said could add up to £800m.

Mazher, who found it all too easy to appeal to the sense of greed in even English royals by dressing up as a free-spending Arab, was able to do what he did because he was always supported by his employers.

He has now been sacked by News UK, the successor to New International, which owned the now defunct News of the World. This is the Sunday newspaper for whom Mazher pulled off many of his spectacular sting operations, including the one involving three Pakistani Test cricketers.

A News UK spokesman said: "Mazher has led scores of successful investigations during his 25-year career with the company. His work has led to the exposure of criminality and wrongdoing. It is a source of great regret that his time with the company should end in this manner."

The spokesman added: "We have noted the threats made after Mazher's conviction of civil claims against this company in relation to his previous work. Should such claims be brought, they will be vigorously defended."

In mitigation, John Kelsey-Fry QC, had said Mazher stood before the court as a "very frightened man".

Of the divorced father-of-one, Kelsey-Fry said: "He has brought catastrophe upon himself and a lifetime's work will be forever tarnished."

Following the sentence, some of Mazher's alleged sting victims gathered outside the Old Bailey to call on Parliament to "cleanse this stain on our democracy once and for all".