The Collopys first got involved in the illicit drug trade in the late 1990s just as the notorious Limerick gang feud began to explode, writes David Raleigh.
The family, from St Mary's Park, became involved with their criminal neighbours the Keanes, which at the time was headed up by brothers Christy and Kieran, who operated a lucrative drug gang.
"The story goes the Collopy gang found a consignment of drugs belonging to the Keanes, which they sold on," a security source explained.
"The Keanes were angry, but they realised the Collopy gang was adept at moving on product onto the streets quickly - so they enlisted the Collopy gang to work for them. That was in the late nineties."
Christy Keane - who served part of a 10-year jail sentence for possession of €250,000 worth of cannabis - survived a second attempted hit of his life last year when two gunmen fired several shots from close range, seriously injuring him.
His brother Kieran was not so lucky - he was kidnapped and tortured and shot in the head in January 2003.
At the height of the Limerick feud, the "Collopy gang stepped back from it", and let the Keanes fight out a turf war against the McCarthy's from Moyross and their cousins, the Dundons, who operated across the city in Ballinacurra Weston.
As the feud rumbled on, the Collopys concentrated solely on selling drugs to wholesalers who in turn fed it to street dealers for €25 a deal.
With Christy in jail and Kieran murdered, the Collopys took control of the drugs market in their St Mary's Park stronghold.
However, after years of evading prosecution they slipped up and were caught themselves packaging heroin during a planned Garda raid, and jailed for eight years today.
The source described the jailing of Brian and Kieran Collopy as "good news" for the people of Limerick, but they added, others will "step in" to fill the gap.
They explained there were up to four operators selling heroin in Limerick.
"There are about 15 to 20 key players. Some gangs are smaller than others...but jailing the Collopy brothers will make a difference alright - it sends out the right message," the source said.
Despite the Collopy godfathers been sent down for eight years, the source confirmed the gang "still have people working for them".
"It's business as usual," they said.
The source explained there are "three or four offshoots" of the drug gangs operating in Limerick, which include "five or six guys at the top of each gang".
They described the heroin epidemic in Limerick as a "scourge".
"You only have to walk the streets of Limerick to see there is a large problem. It's simple economics - the demand is there so there is supply."
They explained how Brian and Kieran Collopy operated from the top level of their drug gang.
"You have an ordinary joe soap on the street and he could be selling 10 or 15 deals in his pocket at €25 a piece - he is bottom of the ladder. He's buying around three or four grams of heroin from a wholesaler."
"The wholesaler would buy about an ounce from the Collopy gang. They got it from contacts in Dublin, before they bagged and sold it to the wholesaler."
In 2006 Brian and Kieran's other siblings, Vincent and Jonathan, were jailed for three years each after their arrest following an undercover Garda operation targeting the sale of heroin.
Operation "Clean Street" was put in place after gardaí became concerned about the level of heroin dealing in Limerick city.