Gardaí believe Dubliner Adam Muldoon was beaten and stabbed to death by a person known to him.
The 23-year-old's remains were discovered in a park in Tallaght, Dublin, on Saturday morning. He had suffered multiple stab wounds.
Mr Muldoon, who had cerebral palsy, was known as a rough sleeper. Gardaí believe he had been sleeping in the area of Butler Park where his body was discovered at about 6.30am.
He was a well known and popular figure in the Jobstown area of Tallaght. Originally from the west Dublin suburb, he had spent time in foster care as a child.
A GoFundMe campaign has been established to meet funeral costs. By Sunday afternoon €1,400 of a €5,000 goal had been raised.
“As everyone knows, poor Adam Muldoon was found brutally murdered today in Tallaght,” a message on the funding page said.
“The whole of the Jobstown community is devastated by the loss of such a harmless fella who didn’t have a bad bone in his body.
“We are asking for people to donate towards his funeral expenses so we can give him the best send off that he deserves.”
Gardaí on Sunday morning arrested a teenager and he was being questioned at Tallaght Garda Station.
The suspect, a minor, can be held for up to 24 hours under Section 4 of the Criminal Justice Act, 1984.
While the investigation into Mr Muldoon’s murder is still in the early stages gardaí believe he had been drinking in Butler Park late on Friday night.
Detectives are working on the theory Mr Muldoon was drinking in the park with at least one other person. And at some point a dispute broke out and quickly developed into a fatal assault.
The killer then fled the scene leaving Mr Muldoon’s body laying undiscovered for several hours.
A number of witnesses have told gardaí they heard raised voices coming from the park in the early hours of Saturday morning.
Gardaí suspect the shouting occurred as Mr Muldoon became involved in the fight that would claim his life.
When the victim's remains were found on Saturday morning in Butler Park, in an area off the Cheeverstown Road, gardai sealed off a large section of the park.
The remains were examined in situ by a pathologist before being removed for full post mortem.
A large area of the park remained sealed off through Sunday as members of the Garda Technical Bureau carried out an examination.
Beer cans were taken from the scene for examination. The inquiries so far indicate Mr Muldoon was attacked at the location where his body was found.
Garda sources said the investigation team was hopeful the results of forensic tests carried out on the murdered man’s remains and items taken from the scene would link to the killer to the crime.
Speaking at a Garda press briefing on Saturday afternoon, Supt Ian Lacken made an appeal for any witnesses, who were in the area at the time.
“I would like to appeal to anyone who may have been in the park between 11pm last night and 6.30am this morning and to any motorists who may have been travelling along the Cheeverstown Road who may have information to offer to contact us at Tallaght Garda station or on the Garda confidential line,” he said.
