Gardaí investigating the death of a newborn baby boy in 1984 are conducting house-to-house inquiries on Valentia Island in Co Kerry.
Some 20 members - both uniform and detectives - are involved in the operation.
Hundreds of questionnaires have been handed out to residents across the island and Gardaí have said they expect the canvas to last a number of days.
It relates to the case of Baby John, known as the Kerry Babies case, who was found stabbed several times on White Strand Beach in Caherciveen on April 14th, 1984.
The canvas is part of a cold-case review, announced on January.
Gardaí said investigators have spent over 9,000 hours on the case in the months since.
DNA sampling is also ongoing and investigating Gardai are also renewing their appeal to members of the public for information.
Valentia Island lies just off the mainland and from White Strand Beach.
Gardaí say the canvass is expected to last "for the next couple of days".
They also say there is "no specific line of enquiry" in Valentia - other than proximity to White Strand.
Other areas in the future may be targeted for specific canvas, they add.
Superintendent Flor Murphy from Killarney is leading the investigation.
He says: "The investigation into Baby John is continuing.
"Significant work has been undertaken since January by the local investigation team supported by the Serious Crime Review Team.
"Over 9,000 investigative hours have been expended on the investigation and 225 separate lines of enquiry are being actively progressed.
"Selective DNA sampling is ongoing and this is a key focus of the investigation.
"The investigation is still appealing for information from the public.
"Someone, somewhere knows"
"We still believe that members of the community in south Kerry have information about the identity of the mother of Baby John.
"Baby John lived for five days so someone, somewhere knows about his very short life.
"Someone is Baby John's mother. Someone is Baby John's father. Someone knew his mother or father.
"People have carried a lot of pain and hurt over the last 30 years.
"This is an opportunity for them to help bring closure to this terrible event and ensure that Baby John receives justice."
He adds: "Even the smallest piece of information could be of major assistance to us.
"Anyone who comes forward will be treated with sensitivity and in the strictest of confidence.
"We have specially trained personnel available who are trained in dealing with difficult and sensitive issues in a compassionate and professional manner.
"After all these years, Baby John deserves the truth."
Anyone with information is asked to contact Caherciveen Gardaí on 066-9473-610.
In January of this year, Gardaí announced a cold case review of the investigation.
They also apologised to Joanne Hayes for their treatment of her in the case.
Then 25-year-old Ms Hayes was arrested and confessed to the baby’s murder but later withdrew it.