A woman, 50s, who was arrested by gardaí on suspicion of murder in the Kerry Babies case has been released without charge.
A file will now be prepared for the DPP.
A man, 60s, who was also arrested last night in connection with the same investigation, remains in garda custody and can be held for up to 24 hours.
The pair were arrested in relation to the discovery of the body of a baby boy at White Strand, Caherciveen, Co Kerry, in April 1984.
The baby, who later became known as 'Baby John', was found with multiple stab wounds.
It is understood that they were arrested in South Kerry and are from the area.
An extensive investigation into the death of Baby John has been ongoing since 2018 by gardaí in the Kerry Division supported by the Garda Serious Crime Review Team.
Hundreds of people have been interviewed and over 560 lines of enquiry have been initiated.
On January 16, 2018, gardaí announced a review into the death of Baby John following a Garda apology to Kerry woman Joanne Hayes, who had been wrongly accused of his murder.
Joanne Hayes had given birth to a baby boy, named Shane, on April 13, 1984, on the family farm, but that child died of natural causes and was buried on the property.
In May 1984 she was arrested in connection with the death of 'Baby John'. In October of that year, all charges against Ms Hayes are dropped. She had repeatedly insisted she had no connection whatsoever to the White Strand infant, and DNA tests subsequently proved the truth of her case.
"The arrests are a significant development in this investigation in an effort to establish the truth surrounding the death of Baby John in 1984 and deliver justice for Baby John,” said lead investigator Superintendent Flor Murphy.
“I am again appealing to the public for any information in relation to the death of Baby John in 1984.
“Anyone who comes forward will be treated with sensitivity and compassion.”