The Kinahan cartel are considered the most powerful drugs importation mob in the history of the State, which some estimate could be worth up to €1bn.
The leader of the cartel is Christy Kinahan (59), who is rarely in Ireland and spends most of his time in his €6m luxury villa in the resort of Estepona on the Spanish coast.
Originally from St Theresa's Gardens in Dublin's south inner city, Kinahan built up a number of convictions as a young man and served jail sentences here for heroin trafficking and a fraud-related offence.
It has been widely reported that he spent his time in jail wisely, including completing a university degree and taking language and legal courses, in order to improve his ability to run an international business.
It's understood that he learnt Spanish and Dutch in jail, languages he is now fluent in.
Christy's sons Daniel and Christopher Jnr were arrested by Spanish police in 2010 as part of an international police investigation into the cartel, codenamed Operation Shovel, but neither man was charged with any offence.
Daniel is heavily involved in the promotion of boxing events, runs his own gym, and is a close pal of professional boxer Matthew Macklin, who has no involvement in crime.
The cartel have dozens of criminals working for them, including some of Ireland's most notorious criminals.
These include convicted heroin dealer Greg Lynch (30) and Crumlin criminal Liam Byrne (36), who has convictions for firearms offences and a savage assault.
Another key member of the mob who was also arrested as part of Operation Shovel is John Cunningham (63), who was jailed for the notorious 1986 kidnap of heiress Jennifer Guinness before he relocated to Holland and then Spain. He later become Christy's right-hand man.
There has been infighting within the cartel's ranks, which has seen three murders since September 2013.
These are the murders of Gary Hutch (34) in Spain last year, almost exactly a year after Gerard 'Hatchet' Kavanagh (44) was shot dead in a Spanish bar.
Then last March, 'Hatchet's brother Paul Kavanagh(26) was shot dead in a gun attack in Drumcondra.