The five men who were arrested early yesterday in connection with the murder on Thursday of a man in a house in Mulhuddart, Co Dublin, had all been released after questioning by early this morning.
The preliminary results of a post-mortem examination on Mr John Murray (34) showed that he died from head injuries, inflicted either by a knife or beating.
Gardai said yesterday that it was unclear whether Mr Murray had been the intended target of the attack at the house in Parslickstown Green, Mulhuddart. He had been visiting a friend nearby and had gone to the house with his friend and the man's daughter.
The friend left the house later, and Mr Murray, the friend's daughter and a woman remained there watching television until about 3.30 a.m. The woman's baby was also in the house.
Mr Murray had gone to bed in an upstairs bedroom when four men arrived at the house at about 4.30 a.m. It is thought that one of the men waited outside and three ran upstairs and attacked Mr Murray. He was found lying in a pool of blood and was pronounced dead at the scene.
The men, in their 20s, were arrested between 7 a.m. and 8 a.m. yesterday under Section 4 of the Criminal Justice Act, under which they could be questioned for 12 hours.
Gardai are understood to be following a definite line of inquiry and believe that the killing may have been the result of a domestic dispute.
