An innocent 72-year-old man was forced to pay gangsters €10,000 after they threatened to murder his son.
The ruthless gang have moved onto the patch of a jailed gang boss who is a suspect in three murders. They are now extorting the relatives of people who owe them money.
The latest incident occurred earlier this month in Balbriggan, when a thug "with scars on his face" called to the family home of the respected pensioner.
"He banged on the man's door and informed the individual that his son had a drugs debt and also owed the gang money for a stolen jeep," a source said.
"He told the man that unless he got €10,000, he was going to kill the man's son. He gave the elderly man two days to pay up, which the terrified man did.
"He is now living in a state of terror that the criminals will come back knocking on his door," the source added.
It is understood that the debt that the man's son owed was for around €2,000 and that the issue involved a stolen vehicle that had been bought from the same gang who made the threats.
They are a family-based organised Traveller crime gang with strong links to Blanchardstown and Cavan town.
Since the gang boss who operated in the area was locked up at the start of the year, the Traveller gang have become the main players in a very lucrative crime patch that includes a large area of north Co Dublin, including Balbriggan, Lusk and Swords.
Apart from taking over the mobster's drugs rackets, sources said that the rival gang have also moved in on his stolen-car business.
"They would not dream of being involved in the level of activity that they are if that individual was not locked up," a source said.
The jailed gang boss, who is suspected of being behind the murders of Willie Maughan and his partner, was also previously arrested in relation to the murder of Benny Whitehouse, who was shot dead in front of his partner.