This exclusive CCTV picture was filmed last Friday night in Donegal Town, six days after pregnant mum of four Jean Quigley was battered to death at her home in Derry.

But it was only at around 8pm on Tuesday that he was apprehended - and last night he was being treated in Sligo General Hospital after complaining of being "unwell."

A quick-thinking Garda detective made the arrest in the Diamond, Donegal Town after recognising him from a picture.

Cahoon was said to be dishevelled and disorientated and was behaving in an agitated manner.

Our picture shows Cahoon, 36, walking near the town's courthouse. He is carrying a large bottle of orange and a takeaway from a local outlet. The pictured were recorded at 10pm last Friday.

Last night Gardai were trying to piece together his movements between Ms Quigley's death and his arrest by Detective Sheridan.

Gardai were on high alert, one source saying, "He had nowhere to run."
The PSNI had asked the media not to release his details publicly for 'operational reasons'.

However, once the identity of the suspect became common knowledge in Derry, the Derry Journal and the Donegal Democrat decided to do so in the interests of public safety in Donegal. It appeared last night that the decision had paid off.

It was revealed that Cahoon knew Donegal well. He met a previous victim at a club in Letterkenny seven years ago. She was later battered by him.
Lynne McGall was battered and assaulted by Cahoon in 1997.

Cahoon's attack against 18-year-old McGall, and former girlfriend Samantha Brown, were considered so violent that, in 2000, the Appeal Court in Belfast increased his term from three years to five years and three months following a campaign by a newspaper.

Ballyshannon Mayor PJ Branley congratulated the good work of the gardai in their apprehension of Cahoon.

He said: "The hard work and the diligence of the gardai has paid off. This arrest has been a coup for the Donegal gardai and this has been recognised nationally."