The Catholic Diocese of Derry has announced the death of its retired bishop, Dr Séamus Hegarty.

Prior to his appointment there in 1994, he had served for 12 years as Bishop of the neighbouring diocese of Raphoe which comprises most of County Donegal.

The Derry diocese said that the 79-year-old died after an illness in Letterkenny University Hospital in County Donegal. He was a native of Kilcar.

The bulk of the late bishop's early career was spent in education.

By the time he was ordained a priest in 1966, he spoke Irish and German fluently and  began teaching in Coláiste na Croise Naofa, in the small Gaeltacht town of Falcarragh in north-west Donegal.

He served as college president between 1971 and 1981 and was credited with the establishment of Pobalscoil Chloich Cheannfhaola in 1973 where he was appointed principal.

But his legacy as bishop of Raphoe was damaged by failures to adequately confront a pattern of clerical child abuse in the diocese.

In 2011, he and both his predecessor and successor -  Bishops Anthony McFeely  (who served from 1965 to 1982) and Philip Boyce, respectively -  were criticised in a report by the church-established National Board for the Protection of Children in the Catholic Church here (NBPCCCI).