The Queensland government has put forward a $250,000 reward for information into the murder of Jason Guise – a man found dumped in a sewage tank on Brisbane’s bayside in 2019.

Mr Guise was last seen on Charlotte Street, Wynnum on April 21, 2019, when he visited a food truck, before being spotted on CCTV riding a bicycle past the Waterloo Hotel on Berrima Street about 7.20pm.

The 45-year-old’s body was found in a pit within a sewage treatment plant nearly three weeks later when maintenance workers made the gruesome discovery during routine checks.

Police said he could have been in the holding tank for several days.

Detective Acting Inspector Mark Mooney said Mr Guise’s family were gravely concerned over his death.

“Jason’s family have been deeply concerned,” he said.

“His father Barry, who lives in Western Sydney, has contacted investigators on a regular basis and still has great concerns over Jason’s death”.

Timeline of Mr Guise’s disappearance

Detective Acting Inspector Mooney said anyone with information before, during or after Mr Guise’s death, should urgently come forward.

“We believe around 2.43pm on the 21st of April 2019, Jason was present at the 7-11 on Tingal Road in Wynnum,” he said.

“We have him on CCTV footage at about 6.38pm walking past the Woolworths at Florence Street at Wynnum.”

Investigators believed Mr Guise returned to his nearby residence at Bride Street before receiving a free meal from a van on Tingal Road.

“We believe he has obtained a food package from that location and left there on a push bike.

“He has [ridden] up Berrima Street near the Waterloo Bay Hotel where we have him again on footage at 7.21pm.

“This is our last sighting of Jason.”

Mr Guise is thought to have returned home to change one last time, with the clothes found on his body different to those he was seen in on the Waterloo Bay Hotel footage.

Detective Acting Inspector Mooney said he strongly believed Mr Guise died a short time after.

Jason’s father Barry Guise is pleading for anyone with information to come forward. Photo: ABC News

Multiple people involved

Investigators said they believed multiple people were involved in Mr Guise’s death.

Detective Acting Inspector Mooney said a $250,000 reward, and appropriate indemnity for any accomplice, not involved in committing the crime, was on offer for anyone with information.

“We believe he’s died elsewhere and that multiple people have transported him,” he said.

“We believe that because of his body weight and size, and to get to the location and even access the sewer in order to place him in the sewer as well.

“The indemnity offered today is of significant value and we appeal for anyone that may be present at that time to come forward.

“Jason’s family and friends have the right and deserve to know what happened to Jason on that day, and if you have that information we urge you to come forward right now.”

-ABC