A 51-year-old former soldier is expected to appear at Naas District Court this morning charged with the murder of Ms Phyllis Murphy who was raped and strangled in Co Kildare almost 20 years ago.
The man, who has recently been a factory worker, was arrested by detectives investigating the random killings of women in the Wicklow Mountains and eastern Midlands over the past 20 years.
He is married with a grown family and lives in Kildare. He was one of a large number of suspects questioned at the time about Ms Murphy's murder.
Ms Murphy (23) was abducted, raped and strangled shortly before Christmas 1979.
Her naked body was found partially hidden in pine forest at the bottom of the Wicklow Gap four weeks later.
It is understood gardai have retained samples taken from Ms Murphy's body and blood samples taken from some 300 men who were questioned at the time about her murder.
The arrest is the first breakthrough in a major Garda investigation which started last summer after Ms Deirdre Jacob, a 19-year-old student at home from university in England, was abducted from a country road near her home at Newbridge, Co Kildare, and disappeared. She is presumed murdered.
Since the Garda Commissioner, Mr Pat Byrne, last year ordered the reinvestigation of a number of cases where women disappeared in the east midlands and Wicklow areas, the case of Ms Murphy has become central to the investigation, mainly because of the forensic evidence available.
Blood samples taken at the time were sent last year for DNA analysis at a laboratory in England. It is understood that about 20 samples were sent for testing. Several weeks ago one showed a match with a sample of semen taken from Ms Murphy's body.
As a result the former soldier and another man, also a retired soldier who had provided an alibi for his movements at the time of Ms Murphy's disappearance, were arrested in Kildare yesterday morning.
Both were arrested under Section 4 of the 1989 Criminal Justice Act which allows for a person's detention for questioning for a total of 12 hours. Yesterday evening, the Director of Public Prosecutions gave a direction that one man be charged with murdering Ms Murphy.
The man who was questioned about Ms Murphy's murder served in the Army from 1966 to 1979, when he retired and began work as a security guard. He retired at the rank of sergeant.
Ms Murphy was on her way home to Kildare with Christmas presents for her family when she disappeared. She was last seen waiting for a bus near the Keadeen Hotel outside Newbridge.
It is believed she was given a lift by a man who then attacked her at Galligan's Cut in the Curragh, killed her and dumped her body almost 20 miles away in the Wicklow Gap.