The body of Australian man Daniel O'Keeffe, who was thought to be missing for almost five years, was found in a cavity underneath the house, a family friend has said.

Then 24, O'Keeffe was last seen in his family home in Geelong, Victoria, on July 15, 2011.

One of his sisters, Loren O'Keeffe, launched an extensive nationwide search for her brother.

Pat Scala Police at the Highton home after the discovery of human remains.

For a while, it was believed that he may be living among homeless people.



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In November 2011, there were reports of O'Keeffe being seen at a Brisbane medical centre.

Paul Jeffers Loren O'Keeffe founded the Missing Persons Advocacy Network after her brother Dan went missing in 2011.

But on Monday, the family's hopes were dashed after his father Des found his son's bones underneath the house.

More details have now emerged about the circumstances surrounding the discovery.

In a post on the Missing Person Daniel James O'Keeffe Facebook page, a friend has sought to clarify "a few facts around the disappearance".

Posted on Wednesday, the message states the family house was built 20 years ago and the back half was dug out of a limestone hill.

"Dan was found in a tight space between a wall of the house and solid rock earth – a space that is very difficult to access."

It is with heavy hearts that the family and friends of Dan O’Keeffe, update this page to share that Dan’s remains were... Posted by Missing Person - Daniel James O'Keeffe on Sunday, 20 March 2016

The unnamed friend goes on to state that the area where the remains were found was "extremely cool" and would have been "especially cold" in the winter when O'Keeffe disappeared.

The post also acknowledged the community's support towards the family.

"The family is incredibly grateful for the messages of support received from the community. There are no words to adequately express the depth of their grief."

Police are yet to confirm the remains are O'Keeffe's, and have not ruled out foul play in the 24-year-old's death.

"We're treating it at the highest level at this stage, until we satisfy ourselves that there is no suspicious activity," Detective Sergeant Adam Forehan said.

While it has been confirmed the remains belong to an adult, the family will have to await the results of DNA tests to confirm without doubt they are those of O'Keeffe.

Forensic tests could also establish a cause of death.