LATEST: Police have located the body of a 21-year-old Ben Reddich who had drowned while swimming in the Brisbane River at Kookaburra Park in Karana Downs.
Just after 11am Queensland Water Police officers located the body about one nautical mile toward Colleges Crossing from where he went missing.
Investigations are continuing into this incident and police will be preparing a report for the coroner.
Anyone with information which could assist with this matter should contact Crime Stoppers anonymously via 1800 333 000 or crimestoppers.com.au 24hrs a day.
6AM: While police and SES crews were searching for the body of Ben Reddich, friends and family have expressed their grief at the 21-year-old's shock drowning.
The young fitness instructor failed to resurface after he dived into the Brisbane River and swam to fetch a soccer ball that was floating away.
The incident took place on Sunday about 2pm. Mr Reddich had been enjoying the day with mates at Kookaburra Park - a popular fishing spot in Karana Downs.
Father-of-two Darryl Whitehead witnessed the tragedy and said it appeared Mr Reddich had drowned from exhaustion.
"When I caught sight of him, he seemed past the point of struggling and just disappeared below the water's surface," he said.
Since then, the search for Mr Reddich has continued non-stop with water police, swift water rescue teams, the polair helicopter and SES crews all involved.
Mr Reddich's father Andrew said he and his family had been struggling to deal with the sudden and tragic news.
He said his son - an up-and-coming bodybuilding athlete - was a wonderful person with a passion for fitness.
Mass Nutrition Chermside manager Sarah Jade Sliwka had worked with Mr Reddich as a personal trainer at the BST Gym in Rocklea.
"He was a really good kid," she said. "He was kind-hearted and extremely passionate about bodybuilding.
"After I left the gym, we kept in contact. I was shocked when I heard the news, I saw him at the gym only last Saturday."
Ms Sliwka said she hoped Mr Reddich was found soon for his friends' and family's sake.
Body building trainer Mark Ryan said he helped prep Mr Reddich for his first National Amateur Body-Builder's Association and World Fitness Federation show.
On Facebook, Mr Ryan said the young fitness fanatic was "a great guy who had a big future and was taken too early".
"It was an honour to have you on our stage," he wrote.
Inspector Charysse Pond said yesterday police and SES were searching two nautical miles from where Mr Reddich was last seen.
She said water police had a sonar radar on their boat and were mapping the area.
"The biggest challenge is there are a lot of trees, rocks and boulders under the surface," she said. "The search will continue until we find this young man."
Insp Pond said police would be unable to establish what happened to Mr Reddich until he was found and examined by the State Coroner's Office.
She said Mr Reddich's family arrived at Kookaburra Park yesterday to spend some time and grieve at the place where he was last seen.
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