"A number of witnesses were interviewed last night and police have a good understanding of events that led to the man's death," he said.
"A scene examination at the Porchester Rd address where the altercation occurred will commence this morning with the assistance of forensic staff.
"A 38-year-old man is assisting police with enquires and police are not seeking anyone else in connection with the incident."
At the cordoned-off Porchester Rd crime scene, believed to be a halfway house, a forensic team was on site.
An armed police officer stood outside a unit at the rear of the six-unit single-level housing unit, as other officers came and went from the scene.
The dead man reportedly lived at the house, where a number of people were drinking last night, and his attacker was believed to have been visiting.
A neighbour this morning said there was nothing out of the ordinary at the house last night.
"There's always lots of people coming and going. And lots of drinking," she said
A witness told the Herald last night that the man collapsed outside the entrance of the medical centre. He was seeking treatment for what were believed to be stab wounds.
The witness, who did not want to be named, said emergency staff surrounded a person lying on the ground.
After a few minutes, officers and medical staff stopped working on the man.
A white company van standing nearby was thought to have been the vehicle in which the man was brought to the clinic.
Mr Lynch said police were appealing for sightings of a knife or similar sharp instrument in the area around Porchester Rd.
Anyone with relevant information was asked to contact the investigation team on 0508 422 443. Alternatively, information can be provided anonymously through Crimestoppers on 0800 555 111.
