Detectives have released security camera footage showing slain Brisbane man Jason Guise on the day he disappeared before his body was found in a sewage tank this month.
The CCTV vision captured Mr Guise, 45, at a Wynnum service station on the afternoon of April 21, the day he was last seen, and later walking through the Woolworths Wynnum Central car park on Florence Street just after 6.30pm that day.
He was last seen on Charlotte Street in Wynnum on April 21 when he visited a Rosie's food truck about 7pm and spoke to friends there. He was later reported missing by his sister after not contacting family or friends since.
Investigators suspect his body was in the tank at the Wynnum pump plant for days before it was found by council maintenance workers about after noon on May 8 at the Granada Street facility.
Detective Inspector Owen Elloy said police conducted "exhaustive investigations" into Facebook posts from the victim and they were still part of ongoing inquiries.
In the social media posts, Mr Guise claimed his possessions were stolen or sold while he was in jail and he had attacked those he believed were responsible.
"I can't stop thinking about all my stuff that got sold – my car, bikes, TV, clothes, pictures of my kids," one post read.
In a later post, Mr Guise appeared to have used violence when questioning people about his missing possessions.
"It's funny when you catch someone you [have] been looking for and they s— themselves," he said.
"Funny how a punch in the face and all of [a] sudden they remember things. They tell you the truth.
"So you lying grubs, I now know the truth, you can't hide now, you know who I mean use [sic] two."
Inspector Elloy said the Wynnum community was "fantastic" in supplying police with footage from their homes and businesses, including the latest batch of vision released on Friday.
"Service stations and the like, they have fairly good quality electronic equipment and we can rely fairly heavily on it for the identification of different persons," he said.
Inspector Elloy said police were not able to narrow down when Mr Guise died and could not discuss a possible cause of death, but a dozen detectives, including the homicide squad, were involved in the case.
"Difficult is a good word, it is a protracted, convoluted investigation … we’re running a homicide crew here with our detectives and they’re certainly earning their money," he said.
"It’s very difficult in these types of cases to secure any type of evidence regarding the timing of demise."
Officers initially identified the body as that of Mr Guise through tattoos and told his family of their suspicions.
Four trucks were needed to empty the four-by-six-metre tank and retrieve the body.
Investigators appealed for anyone who saw Mr Guise to come forward and hoped the release of extra footage on Friday would jog potential witnesses' memories.
"I dare say there is somewhere out there who has some footage that could be useful to us," Inspector Elloy said.
"On the information we have, Mr Guise went to The Benevolent Society on Charlotte Street and picked up some groceries on the night of the 21st and took them back to his Wynnum address."
Inspector Elloy said it was "an understatement" to say it was a grim crime scene and the maintenance crew, who check the tank every 10-14 days, were "certainly shocked" by the discovery.
Police continue to appeal for witnesses and dashcam vision from Wynnum on April 21, particularly around Charlotte Street.
Detectives were also interested in hearing from anyone who saw suspicious activity near the Wynnum sewage facility between April 21 and May 8.
Anyone with information should contact Policelink on 13 14 44 or Crime Stoppers on 1800 333 000.