Members of jailed garda killer Aaron Brady's "closest inside circle" are expected to be arrested this month in relation to the failed campaign of intimidation that blighted his trial.
Earlier this week four criminals, who have been described by senior sources as "a motley crew of idiots, but dangerous idiots", were arrested by detectives.
At least four more arrests are expected within and without our jail system in this probe.
The development comes as the Herald can reveal that another suspect in the intimidation case fled to the UK before he could be arrested.
Five witnesses did not give evidence in Brady's trial for the capital murder of Garda Adrian Donohoe in 2013, during which there were repeated claims that witnesses were being intimidated.
Following the conviction, it emerged that a video of one witness giving a statement about Aaron Brady to gardaí was circulated on social media with text calling him a "rat" and accusing him of "touting" on his friends.
One of the witnesses who did not give evidence was a man who was arrested and brought before the courts this week.
Two of the intimidation suspects were lifted by detectives in jail while the other two were arrested by National Bureau for Criminal Investigation (NBCI) gardaí at their Dublin homes.
The Herald can reveal that a 46-year-old man who was arrested and brought to Raheny Garda Station is currently serving a two-year suspended jail term in relation to heroin possession.
Also arrested is a 29-year-old career criminal from Darndale who has been homeless in recent times and is suspected of "passing on messages from jail to the outside" for cash.
Yesterday, the Herald revealed that north inner city criminal Glen Holland (37), who is aligned to the Kinahan cartel, was arrested in Mountjoy Prison.
Also arrested in the same jail was Dean Byrne (28), a violent north Dublin criminal with more than 120 convictions. He is currently serving a lengthy sentence for aggravated burglary.
Searches of their cells in July and August were carried out by detectives from the National Bureau of Criminal Investigation backed up by the jail's Operational Support Group in Mountjoy prison.
An illegal mobile phone, a charger and notebooks were seized in a search of Holland's cell in late August.
Holland is serving a six-and-a-half year sentence after pleading guilty to possessing two loaded handguns as well as almost €70,000 worth of cocaine in September, 2010.
He was previously arrested by detectives investigating the murder of Eamon 'The Don' Dunne in April of that year.
He spent more than six years on the run in the UK and Spain before being arrested in Spain in August, 2017, on foot of a European Arrest Warrant.
Holland has 21 previous convictions, including for having a phone in prison for which he was given a consecutive two-months in prison in 2018.
Although he has never been charged with the murder of 'The Don', his drugs and firearms conviction was a direct result of a Garda investigation into the fatal shooting.