A gang of thieves have stolen about 1,000m of heavy copper wire at four locations on the same night in Co Donegal.
The raid is estimated to be the 20th such robbery in the county in the last four years.
It is estimated the raids between Milford and Cranford involved up to a dozen men using heavy cutting equipment.
The raids left dozens of homes in remote regions without phonelines, including pensioners who could not operate their emergency personal alarm systems.
A spokesperson for Eircom confirmed it has compiled a report on the matter and this has been passed on to gardaí.
The estimated weight of the haul is more than 10 tonnes, and is valued at some €10,000 on the black market.
In a number of incidents special machinery was used to splice the copper from its casing.
Garda Insp Michael Harrison has appealed to the public to be vigilant.
“We would ask people who notice workmen near telephone wires out of hours and late at night to contact us.”
He appealed to scrap metal dealers to report anybody trying to sell copper wire illegally.
Although a number of arrests have been made into the thefts in recent months, nobody has been charged with the robberies.