THE priest at the funeral mass of murdered Detective Garda Adrian Donohoe has pleaded to anyone with information: "Please God, turn these people in."
Fr Michael Cusack told the congregation that it is "so true than evil exists", and said the killing is like "Satan laughing at us"."
"And if there is anyone who knows anything about that, if you have any semblance of goodness in you, for God's sake, turn these people in. If not, you're allowing Satan to ruin the lives of more and more people.
"He was a man of honour, who could do this?"
Fr Cusack said members of the force "dance" with Satan on a regular basis.
The priest also strongly criticised government cuts to the force and closure of garda stations.
Fr Michael Cusack said he came from a town in Co Galway where the station had closed and two elderly men had since had their "heads bashed in".
"When it comes to reflecting to the garda presence throughout the whole country, I think it's a good time for there to be serious reflection by all in this country around the need for further policing," he added.
"I think we need to look into the eyes of [his wife] Caroline, look into the eyes of Adrian's parents and allow what is best within us - our humanity - to recognise what evil can do when it's allowed to flourish in a community. My parents are now living in a rural community in Galway that has no police service.
"It only ever had one guard but that one guard brought great security. Since he moved, two men in their 80s have had their heads bashed in, one left without hearing or taste for the rest of his life.
"I see it in the eyes of so many in that village that they go to bed at night in fear. Is that the way we need to treat our brothers and sisters in our care?"
The children of Dt Gda Adrian Donohoe have brought gifts remembering their father to the altar at his funeral service in Dundalk.
Det Gda Donohoe's tricolour draped coffin, with his garda hat on gloves placed on top of it, arrived at the Redemptorist church just after one o'clock, accompanied by almost 2,500 of his garda colleagues.
A number of gifts have been presented, including his GAA jerseys from St Pat's in Lordship and his native Cavan.
Fr Cusack, rector of St Joseph's Redemptorist Church, told the service no one could adequately put into words the pain suffered by his wife Caroline - herself a garda - and their two young children, Amy and Niall
His daughter Amy (7) brought the television remote "she always hid" from her Daddy, "and the mobile phone she always rang to say goodbye when he was on night duty", while son Niall (6) brought the football he used to play with with his father.
Streets around the church came to a standstill as up to 1,500 members of the public stood shoulder to shoulder with 2,500 uniformed gardai. Such was the overflow, it could not be accommodated in a massive outdoor marquee and parish hall that were opened up for the turnout.
President Michael D Higgins, Taoiseach Enda Kenny, several senior government ministers and Cardinal Sean Brady were among scores of dignitaries who came from throughout Ireland, on both sides of the border, to pay their respects.
Garda Commissioner Martin Callinan spoke towards the end of the funeral and reassured mourners that the killers will be found.
"No words can adequately express the great sense of loss and revulsion felt by the Donohoe family, the family of An Garda Siochana and indeed the wider public in learning about the cold blooded murder of Detective Garda Adrian Donohoe last Friday night," he said.
"We, Adrian's colleagues, are committed to ensuring that we bring the perpetrators responsible for this callous crime to justice.
"Our resolve is strengthened by the overwhelming support from the President of Ireland, the Government and members of the public."
The Commissioner praised the public for the outpouring of solidarity seen right across the country with messages of sympathy and support being sent to police in stations in every county and online.
"To the local community in the Dundalk and Cooley peninsula, we are forever in your debt for the outstanding generosity you have shown to the Donohoe family and An Garda Siochana at this most difficult time," he said.
"Adrian, Detective Garda, husband, father, son, brother, colleague, community leader, GAA man, friend, we will never forget you."
Mr Donohoe, murdered as he escorted staff with cash from his local credit union, is the first police officer shot dead in Ireland for 17 years since garda Jerry McCabe was gunned down by an IRA gang in a post office raid.
Mr McCabe's wife Ann joined mourners in Dundalk today.
A reward of €50,000 has been offered for information that leads to the arrest and prosecution of the gang involved in Mr Donohoe's murder.
The money was put forward by the Irish League of Credit Unions, which represents credit unions in the Republic of Ireland and Northern Ireland.
Michael Cusack said Mr Donohoe was a loyal, honest, virtuous and faithful man who laid down his life for his community.
"The whole country is gutted by what has happened," he said.
Mr Cusack said the murdered detective was the perfect role model for everybody and the callous mowing down of his innocent life was a reminder that there was good and evil.
"So many people today no longer offer their services freely to the community but Adrian always did," he said.
The rector told Mr Donohoe's wife there were no words that could bring her husband and the father of her children back, but he hoped the support of her family, friends as well as colleagues in the Garda and the GAA would give her some comfort.
Detective Garda Joe Ryan, who was on duty with Mr Donohoe when he was killed, was among pall bearers who carried his Tricolour-draped coffin, with his Garda cap and gloves atop, into the church.
Uniformed colleagues formed a guard of honour as the cortege arrived to be met by the force's entire senior command, led by Commissioner Callinan.
Inside the hearse were wreaths which spelled out Dad, Brother and Son.
Along with his own family, the chief mourners included Mr Donohoe's parents Peggy and Hugh, his parents-in-law Bridie and Stephen, his sisters May and Anne and brothers Colm, Martin and Alan, as well as his brothers-in-law and sister-in-law.
In a moving eulogy, Mr Donohoe's brother Colm said he died doing the job he loved and was born to do.
"Adrian was incredibly highly regarded for the quality of his work, he was professional to the last and he died doing the job that he was born to do and the job that he loved," Mr Donohoe said.
"Whatever Adrian did, whether it was on the football pitch, as a husband, father, son or a guard, he did it to the best of his ability."
Mr Donohoe told the detective's widow that she was the love of his brother's life.
He said the whole Donohoe family would always be there for her and their children.
"To Caroline, I want to thank you. Thank you for making Adrian the happiest, proudest husband and dad," he said.
"It's plain to see from the love you had for each other, you both met the loves of your lives."
He added that the family took comfort that Adrian had packed so much into his short life.
"He lived to his fullest," he said.
Mr Donohoe also thanked his brother's friends, colleagues and the general public for their support over the last five days.
Mr Donohoe described his brother as both big in stature and big in heart.
He said he was "generous to a fault" and had so much to live for.
Mr Donohoe was buried with full honours at Lordship cemetery on the Cooley peninsula a short distance from his home and the Gaelic Athletic Association club were he trained youngsters.
Gardai have appealed to mourners who were at a wake and funeral last week in the village of Clogherhead in Co Louth for information on a stolen car used in the detective's murder.
The 08-D navy Volkswagen Passat was taken from a home in the village on January 22 and used in the attack on Friday night before being found burnt out beside a forest in south Armagh.
The police killers can expect to serve 40 years in jail if convicted.