For the past 18 months the family of missing Queensland man Robert Martinez had hoped a miracle would bring their beloved son back to them alive.

Those hopes were sadly crushed on Tuesday when police confirmed a skull and other bones found at a property on the outskirts of Rockhampton are Mr Martinez’s remains.

The 26-year-old Rockhampton resident vanished in March last year along with his housemate Chantal Barnett, 27.

Police believe they were murdered.

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In a statement, Mr Martinez’s family said the distressing news was obviously not the outcome they had hoped for.

“As much as we were thinking this may have been Robert, to actually have it confirmed has devastated Rob’s whole family,” said the statement, which was read out by Detective Senior Sergeant Scott Moon at a press conference on Tuesday.

“We were all hoping for a miracle. Robert meant everything to us.

“We still can’t believe this is happening.”

The human bones and Ms Barnett’s handbag were found on a Bowlin Rd property last week, the same property where Mr Martinez’s car and wallet were found last year.

Police have offered a $250,000 reward to anyone who can help solve the case.

After taking more than 400 statements, they believe they know who is responsible for the deaths and have urged anyone with information to come forward.

-AAP