A 75-year-old man is recovering in hospital after being beaten with an iron bar by a raider who escaped with €500.
The aggravated robbery is the second suffered by the retired dock worker over the past three years.
The man, who lives alone and is described as exceptionally private, has repeatedly refused offers to move into sheltered housing or live with family members.
Gardai said it was "a miracle" the pensioner escaped serious injury in the robbery, which took place at 3.30am yesterday at his home off the Rathpeacon Road in Farranree, Cork.
The man had special security bars erected by his doors and windows following the last robbery.
However, it is believed the raider gained entry to the house via a small window in the roof.
The pensioner awoke at 3am to discover the masked raider in his bedroom.
He was repeatedly threatened as the man demanded cash and valuables.
The pensioner was then beaten around the legs with an iron bar by the raider who eventually fled on foot.
The alarm was raised and the pensioner was taken to the Mercy University Hospital (MUH) for treatment.
His injuries are not described as life-threatening but he is expected to be kept in under observation as a precaution for several days.
The man's family were keeping a vigil by his hospital bedside.
Garda sources admitted the man is "deeply shocked" by his ordeal.
"This was a very serious and very cruel attack on a vulnerable elderly person," a Gurranabraher garda source said.
"We would appeal to anyone who might have information about this robbery or who may have seen suspicious activity around the Rathpeacon Road area to contact us."
The raider is described as being in his 20s or 30s and of medium build.
Cork elderly rights campaigner Paddy O'Brien said he was appalled by the latest aggravated robbery.
"Old people are living in a state of fear in this country," he said.
"Many are living in loneliness and fear behind locked doors in their homes."