The priest who celebrated the State funeral of Detective Garda Adrian Donohoe has appealed for anyone with information about his killers to come forward.

Det Garda Donohoe was shot dead during an armed raid at the Lordship Credit Union near Dundalk in Co Louth last month.

Speaking on RTÉ's Marian Finucane show, Fr Michael Cusack said people with information had a duty to assist the investigation into the murder.