Four men have been arrested in Dublin over the murder of Sean McMahon in Tallaght last month.
The four, who range in age from 16 to 44, are being held at Tallaght and Rathfarnham Garda stations.
Mr McMahon (35) was shot in the head as he slept in his home on Donaghmore Avenue on November 14th by a gunman who gained access by the back door.
The father-of-two's body was found by his partner.
The killing was the 18th gun murder in the State this year.
