GARDAI are continuing to investigate an incident on Thursday night when two Limerick gangland criminals were arrested after they were spotted travelling behind a prison van in Dublin.
The men were taken to Ballyfermot Garda Station where they were questioned, but they were later released without charge, as no laws had been broken.
It is understood the men detained are members of the McCarthy-Dundon gang. They have been responsible for a series of feud and drug-related gun crime throughout the past eight years.
Gardai are now trying to ascertain why the men were following the prison van and establish if they were studying the movements of the van as part of the planning for a future escape attempt.