Mark Haddock:Mark Haddock was born in 1968 and raised in the strongly loyalist Mount Vernon estate in north Belfast which has seen some of the worst paramilitary violence of the Troubles.
The young Haddock came under the influence of the UVF and he rose to a senior level in that organisation, becoming an area commander.
There is no agreed figure in the number of paramilitary murders he is said to be associated with, but estimates agree it runs to double figures.
Haddock is also linked to other criminal activity including drug-dealing.
In the 1990s Haddock was recruited as an RUC special branch informer and was paid for his services.
This continued for some years while he continued to commit violence for the UVF, his monthly pay rising at one stage by 60 per cent to £160.
Using Dáil privilege, Labour leader Pat Rabbitte named Haddock as an RUC special branch agent and a serial killer whose victims include Catholic taxi-driver Sharon McKenna in 1993, Catholic builders Gary Convie and Éamon Fox in 1994, the alleged informer Thomas Sheppard in 1996, Presbyterian clergyman Rev David J Templeton in 1997, Billy Harbinson in 1997, Raymond McCord jnr in 1997, former UDA commander Tommy English in 2000, and David Greer in 2000.
It has been reported that Haddock's superior ordered him to carry out the McKenna murder to test him, suspecting that he was already an RUC informant.
In December 2002 Trevor Gowdy, a doorman at a social club in Monkstown, was viciously beaten. Haddock was arrested in 2005 and eventually convicted of causing grievous bodily harm to Gowdy and sentenced to 10 years.
Last May he was shot a number of times, supposedly by former UVF colleagues, but survived.