A 72-year-old man, who emphatically denied he had sexually abused a teenage girl over a three-year period, has been jailed for six years.

Michael Casey of Cois Rioga, Caherconlish, Co Limerick was given concurrent jail terms of six years and four years on a total of 16 charges of the defilement of a child.

The sexual abuse began in 2009 when the now 20-year-old woman was 13.

Casey, who was 63 at the time, was good friends with her father as they both worked in the retail shop trade.

The abuse occurred at a number of locations including the victim's home and at a disused factory in counties Clare and Limerick from June 2009 to December 2011.

The woman said that the sexual incidents became almost routine and would happen regularly, including on the morning of a Junior Cert exam.

The abuse came to light when she confided in a friend in 2012, who told a guidance counsellor at her school.

A complaint was later made to gardaí.

The woman said the abuse had left her deeply traumatised and had led to difficulties in her relationships, and she has needed counselling.

Casey denied the allegations, describing them as lies, fantasy and rubbish.

He returned from Africa, where he was doing charity work, to be interviewed by gardaí when confronted with the allegations.

Sentencing him today at Limerick Circuit Court, Judge Tom O'Donnell said he took into account the age of the victim, the grooming nature of the offences, and that Casey was trusted by the victim's parents.

He said the offences were predatory in nature and the accused took advantage at every opportunity to abuse his victim.

Legal aid was granted in the event of an appeal.