AT MID-MORNING last Wednesday, in the north Dublin suburb of Darndale, a team of 80 gardaí was combing the Tara Court halting site as part of the force’s investigation into a feud between the Real IRA and criminal gangs in the city.

The target was a man believed to have been supplying pipe bombs to the Real IRA to use against the gangs they are feuding with and from which they are trying to extort money.

The Army bomb disposal team was called in to deal with two live pipe bombs. As its members dressed in their full-body blast-proof suits, they were snapped by the photographers standing on the high wall across the road.

In the past four or five years, pipe-bomb attacks have become a staple in the arsenal of dissident and criminal gangs around the country. In 2007 there were 98 call-outs for the Army bomb experts. However, the following year a number of criminal gangs became involved in a feud with a leading INLA figure, in which pipe bombs were frequently used.

While that feud has been quieter in recent years, it effectively ushered in a culture in which criminal gangs started targeting each other using viable and hoax devices.

The Army bomb disposal team call-out rate jumped to 180 in 2008 and rose to 196 in 2009 and to 198 in 2010. In 2011 the call-out rate reached 236, with 70 viable devices attended to. That was the highest level since 1979, at the height of the Troubles.

To date this year there have been 155 call-outs and 71 viable devices have been dealt with, including 13 that had already exploded.

The Garda previously believed dissident organisations were responsible for making many of the devices. However, the proliferation of the bombs in recent years and the ease with which they can be made using instructions from the internet suggests they are being assembled by a large number of criminals.

The devices can take a number of forms. In some cases steel pipes are filled with gun powder and, occasionally, nails or nuts and bolts to maximise damage. A fuse is added to one end, and when it is lit the bomb is thrown at a target.

A variation involves a detonator being fitted so that the device explodes on impact, without a fuse. More sophisticated devices involve the use of a timing unit, and a power source that ignites the bomb. Other devices contain chemicals that cause them to explode when they are moved or picked up.

Garda sources say the motives for people being targeted with pipe bombs are varied. “Generally it is to intimidate you and put you and your family in fear and under pressure,” says one source.

“If a device is left outside your house or under your car or whatever, it obviously means you are being targeted and threatened by people with access to explosives, and people who know where you live and what car you drive.

“If they have left an explosive device at your house they have obviously been creeping around outside and that can put people under strain; especially, maybe, the wives or girlfriends of the people who are being targeted. So there’s a number of messages wrapped up in all of that.”

According to another source, “These things don’t even have to exploded to put fear into people; they can do their job just by the people being targeted getting the message that people who can get pipe bombs are out to get them. The threat of violence is just as effective as violence itself in a lot of cases.”

Other sources say many of the devices that have been found in Dublin and Limerick in recent years, as well as around the country, are linked to disputes over money.

“It can be dissidents trying to extort money from drug dealers or even from completely legitimate business people. It can be drug dealers who are feuding with each other simply using a pipe bomb to attack their rivals rather than carry out a drive-by shooting or whatever,” says a source. “And very often it can be a criminal gang targeting someone who owes them money for drugs or from the proceeds of a robbery . . . it’s often a threat to pay up.”