A team of Australian scientists has stumbled upon ancient stone carvings in an East Timorese cave dating back at least 10,000 years.

The findings, just published in the journal Antiquity, follow the discovery in the Lene Hara cave in May 2009.

The team of archaeologists and palaeontologists had been looking for the fossilised remains of extinct giant rats.

But the CSIRO's Dr Ken Aplin accidentally saw the stylised face carvings in the limestone roof.

"One of our East Timorese colleagues was sitting up on top of a big block of limestone and I looked up to see what he was up to and as I did, my head-torch shone across the face of the limestone and I saw these incredible faces engraved on the surface," he said.

"I called out to Sue, the archaeologist, 'Sue - you didn't tell me there were faces engraved here' and she said 'there aren't any' and I went 'come and have a look at this' and her mouth fell open when she saw them."

The Lene Hara carvings, or petroglyphs, are frontal, stylised faces each with eyes, a nose and a mouth. One has a circular headdress with rays that frame the face.

Although stylised engravings of faces occur throughout Melanesia, Australia and the Pacific, the Lene Hara petroglyphs are the only examples that have been dated to the Pleistocene.

No other petroglyphs of faces are known to exist anywhere on the island of Timor.