Louis Watts was knocked unconscious for 1½ hours during the attack in his unit in the Bethesda Village retirement centre in Wiri on Wednesday night.
The ex-crane driver and school teacher spent much of yesterday talking to police from his hospital bed about the attack. He had broken facial bones, bruising to the eyes and cuts to the back of his head.
Detective Senior Sergeant Karyn Malthus said Mr Watts' condition had now improved.
"He is able to get up and walk around," she said.
"However, he is still in pain and finds it incredibly difficult to talk. The day spent with police yesterday has tired him out."
Ms Malthus said Mr Watts, who lives by himself in his unit, was attacked when he confronted an intruder about 7.30pm on Wednesday.
"It seems the offender punched the victim at least once, causing him to be knocked unconscious for about 1½ hours," Ms Malthus said.
"We believe a laptop and camera were stolen from the address and I warn anyone who may now be in possession of these items that they risk being associated with this serious assault on a vulnerable elderly man."
Ms Malthus said the offender was a "portly" Maori or Polynesian man, believed to be middle aged. There were also reports of a suspicious male in the retirement village earlier that evening.
Dozens of potential suspects had been established following information from the public and police work, and Ms Malthus said police were working through them.
A scene examination had finished and forensic scientists were analysing evidence found in the unit.
Anyone with information was asked to call police.
Jon Marshall, chief executive officer of Bethesda Village, said the residents and management were shocked.
"The safety and security of the residents at Bethesda Village is paramount," he said.
"Our current concern is the well-being and full recovery of Mr Watts and offering support to all our residents who are naturally very upset by this event.
"We are taking the situation very seriously and will continue to work closely with the police to find the attacker."
Mr Watts' son-in-law Keith Oddy, 64, didn't think the security at Bethesda Village was to blame.
"The security there is very good. He had his own unit within the retirement village, and I can only sing their praises on what they've done before and since. They're doing a great job to make everybody feel comfortable.
"But if anybody wants to break, in you know they'll do it anyway."
