He was interviewed briefly last night and police hoped to speak with him again this afternoon, he said, to try and paint a better picture of what happened.
It wasn't clear if anyone else was involve in the incident, Mr Scott said.
"We believe the two men who live there are friends. We need to determine if anybody has got in [to their building] and how they got in.
"We don't know how the injuries have been inflicted at this stage. We haven't been able to ascertain how or why [the man] died yet. To me, it's a suspicious death.
"We've got to keep an open mind and are looking for any weapons that may have been used. "
Anybody in the area last night who saw or heard anything is encouraged to call the police, Mr Scott said.
Earlier, police said they had launched a homicide inquiry after the man died following his discovery in a serious condition at a property in Kelston about 9.30pm.
Despite the efforts of ambulance staff, they were unable to save him.
In later release today, police described the death as a suspicious and said a post-mortem examination would be carried out on the dead man today.
Employees at neighbouring offices in the industrial area, which include a large Spotless premises, were being spoken to by police.
Police and ESR teams were gathering evidence at the scene this morning.
A tarpaulin has been covering a section of the car park shared by many offices.
"This investigation is still in its very early stages," said Detective Inspector Bruce Scott of Waitemata police.
"We are in the process of gathering evidence at the scene and are very keen to speak with anyone who believes they may have information relating to the case."
The name of the dead man would be released later.
Anyone with information about the incident can contact police on 09 5712800 or call Crimestoppers anonymously on 0800 555111.
