Key witnesses are yet to come forward to help find the person responsible for the brutal bashing death of a grandfather on a morning walk in Noosa.
Police have issued an appeal for public help a day after emergency crews found John Campbell Kerr unconscious with head injuries on a beachfront path in the Queensland holiday town.
Bystanders tried to help before paramedics arrived, but the 87-year-old died at the scene following the early morning attack.
A 27-year-old Gympie man was arrested about 100 metres away and charged with seriously assaulting a 69-year-old man on the tourist strip about the same time.
Detective Inspector Chris Toohey said Mr Kerr was a loving father and grandfather with nine grandchildren.
The former agricultural consultant was an avid golfer and had a lot of friends and associates in the community.
"We know there are witnesses that have not yet come forward," Det Insp Toohey said.
"And it is important for the investigation for Mr Kerr to speak with all persons who were present in and around Noosa Woods yesterday morning."
Det Insp Toohey said police were investigating the alleged assaults as separate incidents, but he added there was one known person of interest.
Mr Kerr and the 69-year-old man did not know each other and were not together at the time, Det Insp Toohey said.
There was no evidence of a weapon being used in either assault.
Officers want to hear from anyone who saw a man in various stages of undress anywhere near Hastings Street or walking into the Noosa Woods pathways between 5am and 7am on Sunday.
"One of our avenues is that the male person was naked at the time of the assault and in varying stages of undress," Det Insp Toohey said.
Police are still collating CCTV from the area but have no footage of either incident occurring.
Mr Kerr's family released a photo of him in the hope it would encourage more witnesses to come forward.
Det Insp Toohey said it was upsetting for members of the public to come across the seriously injured man.
"It's very confronting for the community that they came across that," he said.
"I will say, though, they attended to Mr Kerr extremely well and as a community we should thank them for their efforts."