The E4A was an intelligence-gathering unit within 'E' Department of the

Royal Ulster Constabulary The Royal Ulster Constabulary (RUC) was the police force in Northern Ireland from 1922 to 2001. It was founded on 1 June 1922 as a successor to the Royal Irish Constabulary (RIC) Richard Doherty, ''The Thin Green Line – The History of the ...

, probably established in 1978. It was primarily made up of police officers who conducted surveillance to be acted on by

RUC Special Branch RUC Special Branch was the Special Branch of the Royal Ulster Constabulary, and was heavily involved in the British state effort during the Troubles, especially against the Provisional Irish Republican Army The Provisional Irish Republica ...

(E4C). E4A was supported by the

Headquarters Mobile Support Unit The Headquarters Mobile Support Unit (HMSU) is the police tactical unit of the Police Service of Northern Ireland (PSNI). The HMSU was originally formed in the then Royal Ulster Constabulary (RUC) part of RUC Special Branch and was involved in s ...

(now part of Special Operations Branch) and targeted paramilitary groups, primarily the

Provisional IRA The Provisional Irish Republican Army (Provisional IRA), officially known as the Irish Republican Army (IRA; ) and informally known as the Provos, was an Irish republican paramilitary force that sought to end British rule in Northern Ireland ...

.Coogan, Tim Pat (2002). ''The troubles: Ireland's ordeal, 1966-1996, and the search for peace''. Tim Pat Coogan. Palgrave Macmillan, p. 347.

References

{{DEFAULTSORT:E4a Royal Ulster Constabulary 1978 establishments in Northern Ireland 2001 disestablishments in Northern Ireland Terrorism in Northern Ireland Counterterrorism in the United Kingdom