You don't expect to get a human body. We've talked about it - you know, what if - but you don't really expect it

Fisherman Robert Van Lawick

The gruesome discovery was made after the fishermen who caught the three-metre (10-feet) long shark opened up its stomach.

The remains, including a skull, arm and pelvis, have been taken away for a post mortem.

Police are contacting experts to find out about digestion rates, currents and tides to try and work out how far away the shark was when it ate its grisly meal.

A similar case was recorded in 1936 when a Tiger shark caught and moved to an aquarium in Sydney regurgitated a human arm found to be that of a murder victim.

Natural or unnatural death?

An autopsy on the remains in this most recent case is scheduled for Tuesday.

"We've got to look at DNA, dental records, perhaps facial reconstruction. We don't know how long it's been in the water and we don't know how long it's been in the shark," Lake Macquarie police Detective Sergeant Murray Lundberg said. "We're going to have to search unsolved homicides."

It is not clear whether the victim was dead or alive when eaten by the shark.

Robert Van Lawick, one of the four members of a game fishing club who caught the shark, said on Monday: "You don't expect to get a human body.

"We've talked about it - you know, what if - but you don't really expect it."

Fatal shark attacks are fairly rare in Australia. Although three swimmers were all bitten last year they all survived. The last recorded fatal attacks were in 2000, when there were three.