A drug dealer targeted in a series of raids on the Kinahan cartel is also suspected of supplying mobile phones to the gang's associates in prison.
Detectives searched seven homes this week and seized a number of encrypted devices linked to the cartel's north inner city associates.
The young criminals targeted are closely connected to senior cartel member Gary Finnegan but are considered "lower-level" operators.
The Herald has learned that a heroin dealer targeted in the raids was also recently caught with five mobile phones.
The devices were found after he was arrested on suspicion of drug dealing, and gardai suspect the phones were to be delivered to cartel members in Mountjoy.
"He was lifted for drugs and found with the small phones. The belief is that they were to be thrown over the prison wall, which is an old and rarely used tactic in this day and age," the source said.
This man, in his mid-20s and from the East Wall area, is also a close associate of a north Dublin criminal suspected of carrying out a shocking murder recently - the details of which cannot be specified for legal reasons.
On Wednesday, detectives from the Drugs and Organised Crime Bureau raided seven homes in Dublin city centre as part of an operation to disrupt the cartel's inner city network.
They were supported by members of the Special Crime Task Force and gardai from the North Central Division.
During the searches, several encrypted phones were recovered, as well as a small quantity of heroin.
Gardai are hopeful that examinations of the encrypted devices will shed light on connections between the cartel and offer fresh intelligence.
A 24-year-old was arrested on suspicion of drug trafficking but later released without charge.
Two of the targets of the operation are suspected of being used as guns-for-hire, and have been quizzed over foiled hits, including the attempted murder of Jonathan Hutch.
Assistant Commissioner John O'Driscoll said the searches provided evidence of the "unrelenting efforts to dismantle organised crime groups that are involved in drug trafficking and a wide range of other criminality, and who are attempting to murder particular people".