A man whose body was found in a sewage holding tank vanished from his Brisbane home more than a fortnight ago and had recently spent time in jail.

A major homicide investigation is underway after maintenance workers found the remains of Jason Guise, 45, at a Wynnum sewage pumping plant on Wednesday.

Police say he was last seen at his Wynnum home on April 21. However, they only began looking for him at the weekend after his sister, who lives interstate, raised the alarm.

Officers won’t say if they believe Mr Guise died at the plant, or was dumped there. They have not revealed the cause of death, with a post-mortem examination to be done on Thursday.

In a Facebook post from April 10, Mr Guise spoke of property being stolen from him.

“It’s funny when you catch someone you been looking for and they shit themselves. And all you want is answers to some questions you have ABOUT all the things you own that was SOLD or STOLEN from me when I (was in) jail,” he wrote.

“Funny how a punch in the face and all of sudden they remember things. They tell you the truth.so you lieing GRUB’S (sic) I Now know the truth …u carnt (sic) hide now….You know who I mean use two (sic).”

Jason Guise, whose body was found in a Queensland sewage tank. Photo: AAP

Police divers spent hours working to extract Mr Guise’s body – a difficult mission that required the removal of four truckloads of liquid from the six-metre deep tank.

Detective Inspector Owen Elloy has appealed for any footage people might have from Wynnum’s Charlotte Street area.

Mr Guise had collected groceries from a benevolent society in that street around the time he vanished, and had taken them back to his home, one street over in Bride Street.

Inspector Elloy said people who lived with Mr Guise had been “a great deal of assistance” to police.

“The investigation is progressing very well,” he said, with 20 detectives and about a dozen forensic and other specialist officers on the case.

Mr Guise had lived in the Wynnum area, in Brisbane’s east, since March.

Inspector Elloy said the pumping station was visited by maintenance crews every 10-14 days.

“Certainly the maintenance crew, I think they were certainly shocked by what they found,” he said.

“It’s nowhere near as secure as you’re obviously thinking. Certainly the gates aren’t overly secure.”

Police have spoken to Mr Guise’s father, after using tattoos on the body to identify him.

-AAP