An additional 36 sets of infant remains have been recovered during forensic excavations at the site of a former mother and baby home in Tuam, Co Galway.

This latest discovery brings the total number of infant remains found by the Office of the Director of Authorised Intervention Tuam (ODAIT) to 69 since work commenced in July.

The ongoing excavation at St Mary’s mother and baby home aims to identify the infants who died there between 1925 and 1961.

In 2014, research led by local historian Catherine Corless indicated that 796 babies and young children were buried in a sewage system at the Co Galway institution across that time period.

In Friday’s update, which covers the period from January 29 to March 31, the ODAIT said the excavation indicated the infants were buried in coffins which have since decayed.

It said the evidence shows the majority of coffins were of a traditional design and painted white.

In a “small number” of cases, two or three infants were buried in the same coffin.

It said the remains were found in part of the area labelled as “burial ground” in historical documents, and that forensic evidence is “consistent with the location being a burial ground from the time of the operation of the Mother and Baby Institution”.

The ODAIT said it is continuing to engage with people who have come forward to offer DNA samples, and since early February five more family DNA samples have been sent to Forensic Science Ireland (FSI).

A total of 33 family DNA samples have now been collected and it said more will be collected in coming weeks in Ireland, the UK and US.

It encouraged anyone who believes they may have a family member buried at the site to contact the organisation and said it will launch a public information campaign in coming months.

ODAIT said it is “nearing completion” of its forensic facility and mortuary in Tuam, which will provide the space for the large-scale analysis and storage of human remains, evidence and artefacts.

A number of artefacts from various time periods have also been uncovered, the update said, including a post-medieval cast copper-alloy decorative keyhole surround.