The Chief Celebrant at Detective Garda Adrian Donohoe's State funeral is calling for a serious reflection on policing.

Thousands of people are attending the requiem mass for the 41-year-old at St. Joseph's Redemptorist Church in Dundalk in Co. Louth.

The father of two was shot dead during a botched robbery at the Lordship Credit Union last Friday night.

2,500 Gardai marched behind his cortege as it arrived at the church from his home shortly after 1pm this afternoon.

Several hundred Gardai from every division in the country will also march behind the cortege as leaves the church.

The President and the Taoiseach are among those attending.

Fr. Michael Cusack says the atrocity should never have happened.

Businesses closed as mark of respect

Many businesses in the town expected to be closed as a mark of respect as the funeral passes by.

A marquee has been erected on the grounds of the church to accommodate the large crowds.

President Michael D. Higgins, Taoiseach Enda Kenny and the Garda Commissioner Martin Callinan will be among those joining the chief mourners - Adrian's wife Caroline, his 6 year old daughter Amy, 7 year old son Niall, father Hugh and mother Peggy.

Two of his brothers Colm and Martin - who are also Gardai - will speak at the service.

Adrian Donohoe will be laid to rest in Lordship Cemetery just a short distance away from where he was murdered.