Two of the six people arrested as part of the investigation into the fatal attack on father-of-six Willie Moorehouse in Bray, Co Wicklow have been released without charge.
The two men, aged in their 20s and 40s, were detained on Monday in the Bray area.
Mr Moorehouse (36) is believed to have gone to the Ballywaltrim area of Bray on Sunday evening for a pre-organised fight.
Gardaí suspect that fight, behind a community centre, was organised in an attempt to settle a drug-related dispute. However, Mr Moorehouse, who lived on the Half Moon Halting Site at Windgates, some 5km south of Bray, was set upon by men with weapons and stabbed to death.
The investigation team has found knives in the area close to the scene of the attack. They are hopeful forensic testing will link these to some of the suspects in the case.
Gardaí on Tuesday searched seven properties at a halting site and arrested a further four suspects - a juvenile, two men in their 20s and one in his 30s. Detectives believe a number of other people were in the area when the fatal altercation arose and are hopeful they may be able to aid the investigation.
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