GARDAI say that criminal gangs have been carrying out surveillance on police stations in south Dublin in a bid to intimidate officers out of giving evidence against them.

Terenure and Rathmines stations have been the subject of surveillance by criminals in the last few months, and officers say gangs were recording registration numbers of garda cars.

“They get somebody to sit outside the station and look at us going in and out,” said one officer. “They know every registration number of our cars, where they’re from, the lot.”

Another senior officer said such surveillance is a form of intimidation and can include individual officers being followed.

“It’s not widespread but it does happen,” he said. “A garda in Limerick was followed home a while ago. It’s just part of what these guys do; they’ll try and intimidate anyone who might give evidence against them.

“It’s a bit worrying when these things happen. They’ve managed to intimidate witnesses, but thankfully not gardai.”

Michael Murray, the chief state solicitor in Limerick, said such tactics were used by gangs in the city and he was not surprised they had spread to other parts of the country.

“We have had cases where the gangs would sit outside a garda’s house as they went off to work. The gardai could do nothing about it,” he said. “The gangs would then follow them or their families.”

One member of a south Dublin gang formerly linked to John Gilligan set up recording equipment at his home and used recorded conversations with gardai to make allegations of harassment.

“They videotape everything on or outside their premises and record every conversation that you have with them,” said one garda. “Then they make complaints about harassment, and the complaints, of course, have to be entertained.”

Gardai say criminal gangs started mounting their own surveillance after the launch of Operation Anvil, a campaign of overt policing aimed at gathering intelligence on gangland figures.

Anvil, which was extended outside Dublin last week by Michael McDowell, the justice minister, reduced crime overall but failed to result in any significant convictions. “Anvil was working brilliantly initially, but now they’ve copped us,” said one garda. “Anvil originated in south Dublin when one superintendent started using roaming checkpoints.

“They looked at a lot of suspect people and snazzy vehicles and discovered that they were attached to burglaries and certain crimes. But now it’s become systematic and the criminals are able to determine what’s what. They’re following our cars around in some cases, not vice versa. They can go around unnoticed, whereas we stand out like a sore thumb. We’re sitting ducks.”

Gardai investigating the gangland murder of Brian Fitzgerald, a Limerick bouncer who was killed in 2002 for refusing to let drug dealers into Doc’s nightclub where he worked, say that the conviction of James Cahill for the killing opens the way for a series of prosecutions of drug dealers in the west of Ireland.

Cahill has offered to testify against figures in the Limerick crime scene in order to enter the garda Witness Security Programme (WSP).

Six leading criminals in Limerick and Clare are named in files sent to the director of public prosecutions (DPP).

They include a Clare businessman who is believed to be the largest supplier of cocaine and cannabis outside Dublin; a Limerick farmer linked to a number of killings; two drug dealers arrested overseas for separate crimes; and two Limerick enforcers with criminal records. One source close to the case said Cahill will be used to corroborate an extensive file submitted by gardai on the gangland figures.

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