Teen killer, 19, sexually assaulted nun, 68, before her body was found outside convent

A warped predator sexually assaulted and murdereda nun who was described as being "in the wrong place at the wrong time". Sister Philomena Lyons was born in Cork,Ireland, but was a beloved member of her community in County Monaghan where she spent 35 years as a teacher.

And it was on the grounds of the local Sacred Heart Convent in Ballybay where she met a cruel end on December 15, 2001. According to the Sunday World, the man responsible for her killing, Herron, could be on his way to freedom. He was spotted leaving Arbour Hill prison in Dublin, with a source telling them he was enjoying some short-term temporary releases.

With that in mind, below we look back on the day of his twisted crime that rocked the Ballybay community.

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It was a bitterly cold morning and Herron, 19 at the time, had not spent the night in his family home in Monaghan. He had reportedly been drinking the evening before December 15 and received a lift to the local shop near the convent at around 8am.

While he was purchasing sweets and soft drinks, Philomena, 68, who was born Christina Lyons, had finished her breakfast, departed the convent, and was waiting to catch a bus into Dublin for a friend's 100th birthday party. The final people to see her alive said she was in a "jovial mood".

She carried two small suitcases and a plastic bag with her, but when colleagues later discovered these discarded by the roadside, they realised something was terribly wrong. But the true horror only emerged when her body was discovered at 5.05pm that evening.

Her remains were found beside a hedge within the convent grounds. It was subsequently established that she had been dragged to the hedge area by her neck. When discovered, her own scarf was wound tightly around her throat and her underwear and tights had been pulled down. There was also bruising on her jaw and neck area and evidence of sexual assault.

She perished after being strangled by her own scarf which was a tragic end for a beloved woman who had also devoted six years of her life teaching in New Jersey, America.

Herron was taken to the Garda station four days later after prints he provided matched the marks on his victim's glasses.

DNA belonging to Philomena was subsequently discovered on his jeans. While under caution, he confessed to the killing. He also stated in his testimony that he sexually assaulted Philomena after the strangulation, before later alleging the assault occurred first before he strangled her in fear she would reveal his identity.

And Patrick Gageby SC said his client expressed his "profound sorry for his actions".

The nun killer pleaded guilty to her murder and received a mandatory term of life imprisonment in 2003. Philomena's family and colleagues said that she would have forgiven him for the "awful crime" and the powerful statement added: "We also forgive him."

Before his life took a destructive turn, Herron, now 45, resided with his parents, had a clean record and held various roles at a plant hire firm, a meat factory and on a building site.

Both the Irish Prison Service and the Parole Board were approached about claims made in this report, but representatives for both stated they do not comment on individual cases.