CRIME gangs are importing signal-jamming devices to disable house and car alarms.
Several consignments of the devices have been seized by customs officers in recent weeks.
The gadgets are imported from China.
Two of the shipments were seized in a controlled delivery to an address in Coolock.
It is believed that some of the jammers have been ordered directly by gangs, while others are intended for sale on the black market.
The seizures were all made by officers based at Dublin Airport over a three-week period.
It is a criminal offence to import or sell jamming devices, which are banned under a "wireless telegraphy interference apparatus" order issued by ComReg, the body responsible for regulating the electronic communications sector.
The jammers can be used for blocking signals such as GSM and GPS, as well as mobile and landline phones and house and car alarms.
Gardai are carrying out tests on one of the bigger devices seized to see if it can be used in cash-in-transit van robberies.
Burglars use the devices to prevent the alarm from sounding and then cut the wires before they break in to a house.
Thieves can also use them on keyless vehicles. The owner walks away thinking they have secured the car by pressing a button without realising the signal has been jammed.
Customs officers told the Irish Independent that this was the first time they had come across the devices here.
The first phone jammer was found in passenger baggage toward the end of October.
A week later, officers discovered two shipments destined for one address.
A few days later, customs officers found eight large jammers, one small signal device, three "super bright" police red flashlights, 20 digital scales, 20 pocket scales, two laser pens, a micro camera and 20 transformers with cable attachments used to power the jammers.
Following the controlled delivery to the Coolock address, the house was raided to establish if there had been other shipments sent there previously, but found none.