A Dublin criminal who had an interaction with murder victim Conor O’Brien (19) before he was killed had previously served a prison term for an attack on a State body.

The website, sundayworld.com, is reporting that the well known criminal is currently being treated as a witness and not a suspect.

The man has given a voluntary statement to gardaí after it emerged he was in direct contact with the teenager hours before he died.

He is known to gardaí for involvement in serious crime and has previously served prison terms both here and in the UK.

This includes a lengthy prison sentence over an attack on a State-linked body.

No arrests have yet been made as part of the murder investigation and at this stage the middle-aged criminal is formally being treated as a witness.

The funeral service for Mr O’Brien, who was about to commence an apprenticeship as a blacksmith. takes place later today in Gorey, County Wexford.