A state funeral for Detective Garda Colm Horkan will take place on Sunday.
The murdered officer will be laid to rest in his home town in Charlestown, Co Mayo.
Det. Gda Colm Horkan was shot up to 15 times in Castlerea, Co Roscommon, on Wednesday night and died at the scene.
The 49-year-old was a Garda for 24 years, largely serving in the west Roscommon area.
A 44-year-old man was arrested at the scene on Wednesday night and remains in Garda custody.
Det. Gda Horkan's funeral mass will take place at St James' Church, Charlestown, at noon, with burial in the adjoining cemetery.
The ceremony will be given formal state honours but will be performed in line with Covid-19 guidelines.
There will also be a formal minute's silence at noon on Sunday in all Garda stations and Garda Headquarters, as all current and retired members show their respects to the long-serving officer.