The Garda cold case unit has been called in to investigate the death of a woman more than 20 years ago after a man came forward claiming to have murdered her.
The body of the woman, who was in her early 40s, was discovered alone in a Dublin flat in 1993 after a night out with friends.
An inquest found that she died of asphyxiation after choking and her death was not regarded as suspicious.
However in a bizarre development, a man walked into a Dublin garda station last July, more than 20 years later, claiming that he had strangled the woman.
It is understood that the man has been receiving psychiatric treatment for some time, and his confession was treated with caution by gardai.
However, detectives have since corroborated some elements of his story after tracking down and interviewing other witnesses who had seen the young woman on the night she died.
The woman's body is now expected to be exhumed so that the state pathologists can conduct a second post mortem.
The woman's name has not been divulged by sources to protect her family, who are understood to be shocked by the developments. They have been kept fully briefed by gardai.
Terenure Garda Station has set up an incident room to coordinate inquiries into the woman's death. The Garda's Serious Crime Review Team, which specialises in investigating historic cases, has also been drafted in to assist local detectives. Investigators are awaiting the outcome of a post mortem before launching a murder inquiry.
Detectives believe that the man may have been with the woman on the night she died. They must first establish whether or not she was murdered, and if she was, whether he was the killer.
A post mortem will be central to those inquiries. The man has given a detailed statement to detectives claiming that that he met the woman on a night out in 1993. He claimed that he returned with her to a flat in Terenure, where he strangled her. He left her in the flat and fled.
He claimed that he didn't know the woman's name, but he did provide approximate dates and a general location of the flat in Terenure where he claimed to have killed her.
Detectives treated his claims with caution. But they established that a woman had died in Terenure in 1993. Her inquest file stated that the cause of death was asphyxiation. Detectives also tracked down witnesses who had seen the woman on the night she died, and corroborated some of his account.
Gardai are now hoping to speak to associates of the man who claims to have committed the murder.
It is understood that the man has no criminal record or history of violence, but if post mortem results suggest the woman was murdered, detectives will take a closer look at his past. The investigation team applied to the Minister for Justice to exhume the young woman's body last month.