Gardai investigating the violent death of 29-year-old father-of-one Vincent Maher plan to arrest more people.
The development comes after a man in his early 20s was questioned at Finglas garda station yesterday after his arrest on Monday night.
He is the third person who was at a house party in Mr Maher's apartment in the early hours of Saturday to be arrested.
Two men who were detained and questioned were released without charge.
Investigations have established that there were around a dozen people at the party in Wellmount Road, Finglas.
A source said: "There will definitely be more arrests in the coming days – gardai are determined to solve this one."
The body of Mr Maher, who was kicked to death, was found on the floor of his bedroom.
It may take several weeks before the investigation can officially be upgraded to murder as gardai are awaiting toxicology tests to determine if the amount of alcohol and drugs in the victim's system contributed to his death.
Originally from Ballymun, Mr Maher is known to have become "extremely messy with drink in him".
Gardai said it was possible he may have survived if someone present during the assault had called for an ambulance.
Men were seen running from the apartment some time after 5am.
His body was discovered by his landlady who visited the apartment at around 11am.
Mr Maher, an unemployed painter, was separated from his partner. His seven-year-old daughter was a regular visitor to his home in the Springmount Apartment Complex.
A neighbour said he had been woken at around 4.30 or 5am by shouting and thumping noises.
He said: "I was woken a few times during the night. It started at around 10 o'clock. It was just a regular party, but then there was shouting, like: 'You better pay for that. You better f***ing pay for that'.
"Then there were a few thumps, loud thumps. But it was like the party went on after that for a while.
"Three fellas jumped over the gate at the entrance to the apartments and ran away, but that was later."
The neighbour described Mr Maher as a "decent guy, he was quiet".