"There are concerns for his welfare as he may require medical attention," the spokesperson said.
Faapaia Fonoilaepa, 29, died in the fatal assault in the area of the Big Barrel liquor store on High St.
A woman who lives near where the fight happened says she could hear someone yelling "help me" at the scene.
The woman, who didn't want to be named, believed it was a gang clash.
She and her 17-year-old son were thinking about calling police when officers arrived at the scene.
"I didn't see what actually happened ... I just wanted to stay inside because you don't want to get involved in that kind of thing," she said.
A female witness to the fatal assault who was being sought by police has been located and she is now assisting with their inquiries.
Police have also reviewed CCTV footage from several nearby buildings and have determined a number of vehicles drove past as the assault unfolded.
"Anyone with any information about this incident or the man described above can phone Lower Hutt Police on (04) 560 2600," the spokesperson said.
"Information can also be provided anonymously via Crimestoppers on 0800 555 111."