Mobster Dessie Dundon has been blamed for a huge surge in drugs at Mountjoy Prison.
This year looks set to see a big increase in drug seizures at the Dublin jail, and sources revealed that the spike began with the arrival of the Dundon-McCarthy gangster.
Dundon (27) was brought to Mountjoy on March 28 after being moved from another jail and prison sources revealed that the supply of drugs had risen since. A Mountjoy source told the Herald that the drugs began appearing almost immediately.
"In the days after he arrived at the prison, the volumes of drugs being thrown over the wall and into the yard jumped dramatically," the source said.
"They were tied to batteries or coins, anything that could get them over the net.
"I don't think the increased supply and Dundon's presence are a coincidence."
The Limerick man, who is serving a sentence for the murder of rival gangster Kieran Keane, could remain at Mount-joy Prison for some time, it is understood.
New figures from the Department show that there were 240 suspected drug seizures this year to April 18. If this trend continues until the end of the year the figure will exceed 700, up on last year's figure of 547.
Fine Gael launched a scathing attack on Justice Minister Dermot Ahern.
Justice spokesman Charlie Flanagan claimed that if "he [Ahern] can't keep prison's safe how can he keep the streets safe? Our prison system is in a state of crisis five years after our Minister for Justice promised us drug-free prisons.
"The political will is not there to make the decisions that have to be made on our prison service. We have people going into prisons clean and emerging with drug addictions.
"We need to prioritise our anti-drug initiatives in prisons by having full-body scanners at the entrances and greater screening measures.
"We also need to train more sniffer dogs to root out drugs in prisons -- the supply of sniffer dogs is wholly insufficient."
Mr Ahern released figures in response to a written Dail question by Mr Flanagan's colleague, Catherine Byrne, Fine Gael spokesperson on the National Drugs Strategy.
Mr Ahern said there were "stringent measures to prevent drugs getting into prisons".