Ken Barrett (born c. 1963) is a Northern Irish former loyalist paramilitary.
 A leading figure within the Ulster Defence Association (UDA), Barrett was involved in collusion between loyalists and the British security forces during the Troubles.
Down Orange Welfare was an Ulster loyalist paramilitary vigilante group active in Northern Ireland during the 1970s.
 Operating in rural areas of County Down, the group faded after failing to win support away from larger groups such as the Ulster Defence Association (UDA) and Ulster Volunteer Force (UVF).
Martin Ingram is the pseudonym of an ex-British Army soldier Ian Hurst who served in the Intelligence Corps and Force Research Unit (FRU).
 He has made a number of allegations about the conduct of the British Army, its operations in Northern Ireland via the FRU, and against figures in the Provisional Irish Republican Army (IRA) and Sinn Féin.
Jackie Coulter (22 May 1954 – 21 August 2000) was a loyalist from Belfast, Northern Ireland who held the rank of lieutenant in the loyalist paramilitary group the Ulster Defence Association (UDA).
 He was killed by the rival loyalist paramilitary organisation the Ulster Volunteer Force (UVF), as the result of a feud within loyalism.
The Ulster Defence Association (abbreviated UDA) is the largest Ulster loyalist paramilitary and vigilante group in Northern Ireland.
 It was formed in September 1971 and undertook a campaign of almost twenty-four years during the Troubles.
 For most of this time it was a legal organisation.
 Its declared goal was to defend Ulster Protestant loyalist areas and to combat Irish republicanism, particularly the Provisional Irish Republican Army (IRA).
 In the 1970s, uniformed UDA members openly patrolled these areas armed with batons and held large marches and rallies.
 Within the UDA was a group tasked with launching paramilitary attacks; it used the covername Ulster Freedom Fighters (UFF) so that the UDA would not be outlawed.
 The British government outlawed the "UFF" in November 1973, but the UDA itself was not proscribed as a terrorist group until August 1992.
Alex Kerr is a Northern Irish former loyalist paramilitary.
 Kerr was a brigadier in the Ulster Defence Association (UDA)'s South Belfast Brigade before becoming one of the two founders of the Loyalist Volunteer Force (LVF).
 He is no longer active in loyalism.
Andrew Robinson is a Northern Irish former loyalist paramilitary leader.
 Robinson held the rank of "Brigadier" in the Ulster Defence Association (UDA) and was leader of the organisation's North Antrim and Londonderry Brigade as well as a member of the UDA's Inner Council.
The Ulster Service Corps (USC) was a loyalist vigilante group with a paramilitary structure active in Northern Ireland in the late 1970s.
 Although short-lived it briefly had a sizeable membership.
 One of a number of small independent loyalist paramilitary groups active in the mid 1970s, alongside the Orange Volunteers, Ulster Volunteer Service Corps, Down Orange Welfare and the Ulster Special Constabulary Association (USCA), the USC was the largest of these minor groups.
Albert "Ginger" Baker (born c. 1951) is a Northern Irish former loyalist and ex-British Army soldier who was convicted of four murders carried out by the Ulster Defence Association (UDA), of which he was a leading member.
 He turned himself in to the police in 1973 after throwing a hand grenade into a bus transporting Catholic workmen in East Belfast, Northern Ireland, which killed one man.
 He admitted to this killing and those of three other Catholics the previous year, as well as 11 armed robberies.
 He was sentenced to 25 years imprisonment for the four murders.
The Loyalist Volunteer Force (LVF) is a small Ulster loyalist paramilitary group in Northern Ireland.
 It was formed by Billy Wright in 1996 when he and his unit split from the Ulster Volunteer Force (UVF) after breaking its ceasefire.
 They had belonged to the UVF's Mid-Ulster Brigade and Wright had been the brigade's commander.
 In a two-year period from August 1996, the LVF waged a paramilitary campaign with the stated goal of combatting Irish republicanism.
 During this time it killed at least 14 people in gun and bomb attacks.
 Almost all of its victims were Catholic civilians who were killed at random.
 The LVF called off its campaign in August 1998 and decommissioned some of its weapons, but in the early 2000s a loyalist feud led to a number of killings.
 Since then, the LVF has been largely inactive, but its members are believed to have been involved in rioting and organized crime.
 In 2015, the security forces stated that the LVF "exists only as a criminal group" in Mid-Ulster and Antrim.

Question: Albert "Ginger" Baker, is a Northern Irish former loyalist and ex-British Army soldier, who was convicted of four murders, carried out by which loyalist paramilitary and vigilante group, in Northern Ireland?
Answer: Ulster Defence Association