SYDNEY - A 120-million-year-old plesiosaur resembling Scotland's loch ness monster and possibly new to science has been discovered in the central Australian outback, it was revealed Monday.

The fossilized bones of the seven-meter (23-feet) reptile was found by a team of four scientists from the south Australian museum in the far north of south Australia state, AFP reported.

But precisely where this cretaceous-period stomping-ground has been kept a closely guarded secret to protect it from the destructive hands of inexperienced dinosaur dealers and souveniring amateurs, the team said.

"Potentially, we're looking at an animal new to science," the leader of the team, paleontologist Ben Kear, told the Australian newspaper, AFP reported.

Whether it is new or not will only be known after the bones are examined and an analysis completed at the museum.

Kear and his colleagues were on their way back from the site to the museum in adelaide and out of mobile telephone range on Monday.

But their colleague, Ben McHenry, said they had gone back to the site at the weekend to excavate the bones which they had originally stumbled on three months ago.

Like other paleontologists, the team has been covering its tracks, re-burying fossils for excavation later and using satellite tracking to relocate the prehistoric trove in an effort to outsmart the poachers.

"Our greatest fear is that we discover something and then we go back to study it and it's gone," said McHenry.

"That has happened several times and it's very disheartening. We're trying to draw least attention to ourselves, which is a shame because finds should be big news for the public, but then the wrong people find out about it."

Experts say plesiosaurs lived between 220 and 65 million years ago during the cretaceous and Jurassic periods.